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    Hard and Soft Tissue Response of Two-Dimensional Nanoparticle Incorporated Biodegradable Polymeric Scaffolds. Rashkow Jason T,Talukdar Yahfi,Lalwani Gaurav,Sitharaman Balaji ACS biomaterials science & engineering Current efforts in the design of bone tissue engineering scaffolds have focused on harnessing the physiochemical properties of two-dimensional organic and inorganic nanoparticles to improve bulk and surface properties of biodegradable polymers. Herein, we investigate the hard and soft tissue biocompatibility of two such constructs: 90% porous poly(lactic--glycolic acid) (PLGA) nanocomposite scaffolds incorporated with 0.2 wt % graphene oxide nanoplatelets (GONPs) or molybdenum disulfide nanoplatelets (MSNPs). Scaffolds were implanted in a noncritical sized monocortical defect in the tibia or subcutaneously on the dorsum of a rat model for 2 or 6 weeks. Hard and soft tissue biocompatibility of the nanoparticle reinforced scaffolds was comparable to that of the PLGA control. In addition, 2 weeks after implantation, significantly less bone growth (∼35%) was observed for the PLGA group compared to that of the empty defect group; it was not observed for the experimental groups which showed 20% and 15% greater bone growth compared to that of the PLGA group. This may indicate that the nanoparticles do play a role in assisting bone regeneration. Taken together, the results suggest that scaffolds incorporated with GONPs or MSNPs show promise for bone tissue engineering applications. 10.1021/acsbiomaterials.7b00425
    Antibacterial Activities of Aliphatic Polyester Nanocomposites with Silver Nanoparticles and/or Graphene Oxide Sheets. Liao Chengzhu,Li Yuchao,Tjong Sie Chin Nanomaterials (Basel, Switzerland) Aliphatic polyesters such as poly(lactic acid) (PLA), polycaprolactone (PCL) and poly(lactic-co-glycolic) acid (PLGA) copolymers have been widely used as biomaterials for tissue engineering applications including: bone fixation devices, bone scaffolds, and wound dressings in orthopedics. However, biodegradable aliphatic polyesters are prone to bacterial infections due to the lack of antibacterial moieties in their macromolecular chains. In this respect, silver nanoparticles (AgNPs), graphene oxide (GO) sheets and AgNPs-GO hybrids can be used as reinforcing nanofillers for aliphatic polyesters in forming antimicrobial nanocomposites. However, polymeric matrix materials immobilize nanofillers to a large extent so that they cannot penetrate bacterial membrane into cytoplasm as in the case of colloidal nanoparticles or nanosheets. Accordingly, loaded GO sheets of aliphatic polyester nanocomposites have lost their antibacterial functions such as nanoknife cutting, blanket wrapping and membrane phospholipid extraction. In contrast, AgNPs fillers of polyester nanocomposites can release silver ions for destroying bacterial cells. Thus, AgNPs fillers are more effective than loaded GO sheets of polyester nanocomposiites in inhibiting bacterial infections. Aliphatic polyester nanocomposites with AgNPs and AgNPs-GO fillers are effective to kill multi-drug resistant bacteria that cause medical device-related infections. 10.3390/nano9081102
    Biomineralized Poly(l-lactic--glycolic acid)/Graphene Oxide/Tussah Silk Fibroin Nanofiber Scaffolds with Multiple Orthogonal Layers Enhance Osteoblastic Differentiation of Mesenchymal Stem Cells. Shao Weili,He Jianxin,Wang Qian,Cui Shizhong,Ding Bin ACS biomaterials science & engineering Bone scaffolds with interconnected pores, good mechanical properties, excellent biocompatibility, and osteoinductivity are challenging to fabricate. In this study, we fabricated and characterized the morphology, hydrophilicity, protein adsorptivity, mechanical properties, and fibrous structure of nanofiber scaffolds with multiple, orthogonal layers of composite materials based on poly(l-lactic--glycolic acid) (PLGA), graphene oxide (GO), tussah silk fibroin (TSF), and hydroxyapatite (HA). The data show that incorporation of 1 wt % GO into PLGA/TSF nanofibers significantly decreased the fiber diameter from 321 to 89 nm. On the other hand, incorporation of 10 wt % TSF accelerated the nucleation and growth of HA on composite PLGA/GO scaffolds exposed to simulated body fluid. Furthermore, the compressive modulus and stress of composite scaffolds with GO were 1.7-fold and 0.6-fold higher than those of similar scaffolds without GO. Interestingly, composite scaffolds with multiple orthogonal layers exhibited higher compressive modulus and stress compared to scaffolds with randomly oriented nanofibers. Biological assays indicated that mineralized scaffolds with multiple orthogonal layers significantly enhanced cell adhesion, proliferation, and differentiation of mesenchymal stem cells into osteoblasts. In summary, the data indicate that these scaffolds have excellent cytocompatibility and osteoinductivity and have potential as versatile substrates for bone tissue engineering. 10.1021/acsbiomaterials.6b00533
    Fabrication and Properties of Electrospun Magnetoelectric Graphene/Fe₃O₄/Poly(lactic-co-glycolic acid) Short Nanofibers. Li Ping,Xi Yao,Li Kun,Qi Bing,Zhu Fengnian,Fan Yubo Journal of nanoscience and nanotechnology When used in tissue engineering, polymer nanofibers with magnetic and electrical functionality could promote the growth of tissues and cells by applying magnetic and electric stimulation. Short nanofibers with these properties, which have a high specific surface area and can be arranged through magnetic induction, have potential applications in the fields of materials and biomedical engineering. In this study, poly(lactic-co-glycolic acid) (PLGA) nanofibers with nano-Fe₃O₄ particles were subjected to electrostatic spinning to obtain superparamagnetic Fe₃O₄/PLGA nanofibers. After being processed in a homogenizer, graphene/Fe₃O₄/PLGA short nanofibers with a length of 11.90±2.03 m and a diameter of 256.5±13.7 nm were prepared by deposition. The effects of the PLGA concentration and graphene concentration on the morphology, size and conductivity of short fibers were studied by scanning electron microscopy (SEM) and conductivity testing. The chemical composition of the short fibers was characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The magnetic properties of the short fibers were characterized by using a vibrating sample magnetometer (VSM). Superparamagnetic and conductive PLGA nanofibers with a conductivity of 9.34×10 S/m were obtained for further applications. 10.1166/jnn.2019.16400
    Chitosan/graphene and poly(D, L-lactic-co-glycolic acid)/graphene nano-composites for nerve tissue engineering. Soltani S,Ebrahimian-Hosseinabadi M,Zargar Kharazi A Tissue engineering and regenerative medicine This study aimed at examining and comparing the fabrication process, electrical conductivity, and biological properties of Chitosan/Graphene membranes and poly(D, L-lactic-co-glycolic acid) (PLGA)/Graphene membranes. Nano-composite membranes were made using chitosan or PLGA matrix, and 0.5-1.5 wt.% graphene nano-sheets as the reinforcement material; all the membranes were fabricated through solution casting method. Fourier transform infrared spectroscopy and X-ray diffraction results indicated that the graphene had been uniformly dispersed in polymeric matrix. The membranes with 1.5 wt.% graphene appeared to have the highest value of electrical conductivity among all the examined the membranes and this growth was about 10 in comparison with neat polymers. Since the Chitosan 1.5% graphene membrane was found to have the highest proliferation after 72 hours by MTT [3-(4, 5-di-methylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] assay of PC12 cell line (<0.05), it is promising to consider nano-composite membrane for nerve tissue engineering applications. 10.1007/s13770-016-9130-1
    PLGA-based nanofibers with a biomimetic polynoradrenaline sheath for rapid in vivo sampling of tetrodotoxin and sulfonamides in pufferfish. Tang Yijia,Huang Siming,Xu Jianqiao,Ouyang Gangfeng,Liu Yuan Journal of materials chemistry. B Nanomaterials have shown great potential for application in microextraction due to their distinguishing nanoscale architectures and superior physicochemical properties. Herein, novel poly(lactic-co-glycolic acid) (PLGA) solid-phase microextraction (SPME) fibers, which were incorporated with a self-assembled graphene oxide (GO)-coated γ-AlO composite (AlO@GO), were fabricated on stainless steel wires via an electrospinning method. The as-spun nanofibers were further sheathed through the self-polymerization of noradrenaline (NA), an agonist found in oysters, to provide a compatible biointerface and antifouling capacity. Acting as the coating substrate of the as-prepared fibers, PLGA is known for its prominent biocompatibility and biodegradability, while the adsorptive AlO@GO particles helped to increase their loading capacity. The modified PLGA-based electrospun nanofibers exhibited much higher extraction efficiency compared with the thicker polydimethylsiloxane (PDMS) coatings (165 μm) and polyacrylate (PA) coatings (85 μm). Due to the fine biointerface of the PLGA-based nanofibers, a rapid extraction equilibrium was observed and sampling with the custom-made AlO@GO-PLGA@PNA fibers could be accomplished within 15 min. The fibers were then successfully employed for simultaneous in vivo sampling of tetrodotoxin (TTX) and sulfonamides (SAs) in the dorsal-epaxial muscle of living pufferfish (Takifugu obscurus), and satisfactory sensitivities with limits of detection (LODs) in the range of 0.52-2.30 ng g and comparable accuracies to the conventional liquid extraction (LE) method were achieved. In vivo sampling of target pharmaceuticals with the modified nanofibers showed their feasibility for further metabolomics and pharmacokinetics studies in biotissues. 10.1039/c8tb00757h
    Amphiphilic prodrug-decorated graphene oxide as a multi-functional drug delivery system for efficient cancer therapy. Huang Chunzhi,Wu Jilian,Jiang Wei,Liu Ruiling,Li Zhonghao,Luan Yuxia Materials science & engineering. C, Materials for biological applications Graphene oxide (GO) has shown great potential in drug delivery. However, the aqueous stability, non-specific drug release and slow release rate are major problems of the GO-based drug delivery system. Herein, we for the first time integrate the dispersant, stabilizing agent and active targeting carrier into a novel drug delivery system based on GO/PP-SS-DOX nanohybrids. The redox-sensitive PP-SS-DOX prodrug was obtained by conjugating mPEG-PLGA (PP) with doxorubicin (DOX) via disulfide bond. PEG-FA provided active targeting property for the constructed drug delivery system, GO/PP-SS-DOX/PEG-FA. In this demonstrated system, PP-SS-DOX markedly increases the stability in physiological solutions of GO and guarantees the DOX release in the reductive environment (cancerous cells). And PEG-FA helps target to cancerous tissues and induces FR-mediated endocytosis. In vitro drug release exhibited the obvious reductive sensitivity and the cumulative release amount was up to 90%, while 40% in previous reports within 72 h. The in vitro cytotoxicity of targeting nanohybrids was significantly cytotoxic than that of non-targeting nanohybrids. In vivo results displayed that the as-prepared targeting nanohybrids showed efficacious antitumor effect while it had nearly no systemic adverse toxicity on B16 tumor-bearing mice. Therefore, the in vitro and in vivo results indicate that our constructed GO/PP-SS-DOX/PEG-FA drug delivery system is a promising carrier in cancer therapy. 10.1016/j.msec.2018.03.017
    Three-dimensional macroporous graphene scaffolds for tissue engineering. Lalwani Gaurav,D'agati Michael,Gopalan Anu,Rao Manisha,Schneller Jessica,Sitharaman Balaji Journal of biomedical materials research. Part A The assembly of carbon nanomaterials into three-dimensional (3D) porous scaffolds is critical to harness their unique physiochemical properties for tissue engineering and regenerative medicine applications. In this study, we report the fabrication, characterization, and in vitro cytocompatibility of true 3D (>1 mm in all three dimensions), macroscopic (3-8 mm in height and 4-6 mm in diameter), chemically cross-linked graphene scaffolds prepared via radical initiated thermal cross-linking of single- and multiwalled graphene oxide nanoribbons (SWGONRs and MWGONRs). SWGONR and MWGONR scaffolds possess tunable porosity (∼65-80%) and interconnected macro-, micro-, and nanoscale pores. Human adipose derived stem cells (ADSCs) and murine MC3T3 preosteoblast cells show good cell viability on SWGONR and MWGONR scaffolds after 1, 3, and 5 days comparable to 3D poly(lactic-co-glycolic) acid (PLGA) scaffolds. Confocal live-cell imaging showed that cells were metabolically active and could spread on SWGONR and MWGONR scaffolds. Immunofluorescence imaging showed the presence of focal adhesion protein vinculin and expression of cell proliferation marker Ki-67 suggesting that cells could attach and proliferate on SWGONR and MWGONR scaffolds. These results indicate that cross-linked SWGONR and MWGONR scaffolds are cytocompatible and opens-avenues toward the development of 3D multifunctional graphene scaffolds for tissue engineering applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 73-83, 2017. 10.1002/jbm.a.35867
    Fabrication and Application of Novel Porous Scaffold in Situ-Loaded Graphene Oxide and Osteogenic Peptide by Cryogenic 3D Printing for Repairing Critical-Sized Bone Defect. Zhang Yidi,Wang Chong,Fu Li,Ye Shan,Wang Min,Zhou Yanmin Molecules (Basel, Switzerland) Osteogenic peptides have been reported as highly effective in directing mesenchymal stem cell osteogenic differentiation in vitro and bone formation in vivo. Therefore, developing novel biomaterials for the controlled delivery of osteogenic peptides in scaffolds without lowering the peptide's biological activity is highly desirable. To repair a critical-sized bone defect to efficiently achieve personalized bone regeneration, a novel bioactive poly(lactic-co-glycolic acid) (PLGA)/β-tricalcium phosphate (β-TCP) composite scaffold, in which graphene oxide (GO) and bone morphogenetic protein (BMP)-2-like peptide were loaded in situ (PTG/P), was produced by an original cryogenic 3D printing method. The scaffolds were mechanically comparable to human cancellous bone and hierarchically porous. The incorporation of GO further improved the scaffold wettability and mechanical strength. The in situ loaded peptides retained a high level of biological activity for an extended time, and the loading of GO in the scaffold further tuned the peptide release so that it was more sustained. Our in vitro study showed that the PTG/P scaffold promoted rat bone marrow-derived mesenchymal stem cell ingrowth into the scaffold and enhanced osteogenic differentiation. Moreover, the in vivo study indicated that the novel PTG/P scaffold with sustained delivery of the peptide could significantly promote bone regeneration in a critical bone defect. Thus, the novel bioactive PTG/P scaffold with a customized shape, improved mechanical strength, sustainable peptide delivery, and excellent osteogenic ability has great potential in bone tissue regeneration. 10.3390/molecules24091669
    Graphene Oxide Hybridized nHAC/PLGA Scaffolds Facilitate the Proliferation of MC3T3-E1 Cells. Liang Chunyong,Luo Yongchao,Yang Guodong,Xia Dan,Liu Lei,Zhang Xiaomin,Wang Hongshui Nanoscale research letters Biodegradable porous biomaterial scaffolds play a critical role in bone regeneration. In this study, the porous nano-hydroxyapatite/collagen/poly(lactic-co-glycolic acid)/graphene oxide (nHAC/PLGA/GO) composite scaffolds containing different amount of GO were fabricated by freeze-drying method. The results show that the synthesized scaffolds possess a three-dimensional porous structure. GO slightly improves the hydrophilicity of the scaffolds and reinforces their mechanical strength. Young's modulus of the 1.5 wt% GO incorporated scaffold is greatly increased compared to the control sample. The in vitro experiments show that the nHAC/PLGA/GO (1.5 wt%) scaffolds significantly cell adhesion and proliferation of osteoblast cells (MC3T3-E1). This present study indicates that the nHAC/PLGA/GO scaffolds have excellent cytocompatibility and bone regeneration ability, thus it has high potential to be used as scaffolds in the field of bone tissue engineering. 10.1186/s11671-018-2432-6
    Stimulating effect of graphene oxide on myogenesis of C2C12 myoblasts on RGD peptide-decorated PLGA nanofiber matrices. Shin Yong Cheol,Lee Jong Ho,Kim Min Jeong,Hong Suck Won,Kim Bongju,Hyun Jung Keun,Choi Yu Suk,Park Jong-Chul,Han Dong-Wook Journal of biological engineering BACKGROUND:In the field of biomedical engineering, many studies have focused on the possible applications of graphene and related nanomaterials due to their potential for use as scaffolds, coating materials and delivery carriers. On the other hand, electrospun nanofiber matrices composed of diverse biocompatible polymers have attracted tremendous attention for tissue engineering and regenerative medicine. However, their combination is intriguing and still challenging. RESULTS:In the present study, we fabricated nanofiber matrices composed of M13 bacteriophage with RGD peptide displayed on its surface (RGD-M13 phage) and poly(lactic-co-glycolic acid, PLGA) and characterized their physicochemical properties. In addition, the effect of graphene oxide (GO) on the cellular behaviors of C2C12 myoblasts, which were cultured on PLGA decorated with RGD-M13 phage (RGD/PLGA) nanofiber matrices, was investigated. Our results revealed that the RGD/PLGA nanofiber matrices have suitable physicochemical properties as a tissue engineering scaffold and the growth of C2C12 myoblasts were significantly enhanced on the matrices. Moreover, the myogenic differentiation of C2C12 myoblasts was substantially stimulated when they were cultured on the RGD/PLGA matrices in the presence of GO. CONCLUSION:In conclusion, these findings propose that the combination of RGD/PLGA nanofiber matrices and GO can be used as a promising strategy for skeletal tissue engineering and regeneration. 10.1186/s13036-015-0020-1
    Magnetic nanoparticles encapsulated into biodegradable microparticles steered with an upgraded magnetic resonance imaging system for tumor chemoembolization. Pouponneau Pierre,Leroux Jean-Christophe,Martel Sylvain Biomaterials In this work, therapeutic magnetic micro carriers (TMMC) guided in real time by a magnetic resonance imaging (MRI) system are proposed as a mean to improve drug delivery to tumor sites. MRI steering constraints and physiological parameters for the chemoembolization of liver tumors were taken into account to design magnetic iron-cobalt nanoparticles encapsulated into biodegradable poly(d,l-lactic-co-glycolic acid) (PLGA) microparticles with the appropriate saturation magnetization (M(s)). FeCo nanoparticles displayed a diameter of 182nm and an M(s) of 209 emicrog(-1). They were coated with a multilayered graphite shell to minimize the reduction of M(s) during the encapsulation steps. FeCo-PLGA microparticles, with a mean diameter of 58 microm and an M(s) of 61emicrog(-1), were steered in a phantom mimicking the hepatic artery and its bifurcation, with a flow in the same order of magnitude as that of the hepatic artery flow. The steering efficiency, defined as the amount of FeCo-PLGA microparticles in the targeted bifurcation channel divided by the total amount of FeCo-PLGA microparticles injected, reached 86%. The data presented in this paper confirms the feasibility of the steering of these TMMC. 10.1016/j.biomaterials.2009.08.005
    Antimicrobial Electrospun Biopolymer Nanofiber Mats Functionalized with Graphene Oxide-Silver Nanocomposites. de Faria Andreia F,Perreault François,Shaulsky Evyatar,Arias Chavez Laura H,Elimelech Menachem ACS applied materials & interfaces Functionalization of electrospun mats with antimicrobial nanomaterials is an attractive strategy to develop polymer coating materials to prevent bacterial colonization on surfaces. In this study we demonstrated a feasible approach to produce antimicrobial electrospun mats through a postfabrication binding of graphene-based nanocomposites to the nanofibers' surface. A mixture of poly(lactide-co-glycolide) (PLGA) and chitosan was electrospun to yield cylindrical and narrow-diameter (356 nm) polymeric fibers. To achieve a robust antimicrobial property, the PLGA-chitosan mats were functionalized with graphene oxide decorated with silver nanoparticles (GO-Ag) via a chemical reaction between the carboxyl groups of graphene and the primary amine functional groups on the PLGA-chitosan fibers using 3-(dimethylamino)propyl-N'-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide as cross-linking agents. The attachment of GO-Ag sheets to the surface of PLGA-chitosan fibers was successfully revealed by scanning and transmission electron images. Upon direct contact with bacterial cells, the PLGA-chitosan mats functionalized with GO-Ag nanocomposites were able to effectively inactivate both Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacteria. Our results suggest that covalent binding of GO-Ag nanocomposites to the surface of PLGA-chitosan mats opens up new opportunities for the production of cost-effective, scalable, and biodegradable coating materials with the ability to hinder microbial proliferation on solid surfaces. 10.1021/acsami.5b01639
    RGD peptide and graphene oxide co-functionalized PLGA nanofiber scaffolds for vascular tissue engineering. Shin Yong Cheol,Kim Jeonghyo,Kim Sung Eun,Song Su-Jin,Hong Suck Won,Oh Jin-Woo,Lee Jaebeom,Park Jong-Chul,Hyon Suong-Hyu,Han Dong-Wook Regenerative biomaterials In recent years, much research has been suggested and examined for the development of tissue engineering scaffolds to promote cellular behaviors. In our study, RGD peptide and graphene oxide (GO) co-functionalized poly(lactide--glycolide, PLGA) (RGD-GO-PLGA) nanofiber mats were fabricated via electrospinning, and their physicochemical and thermal properties were characterized to explore their potential as biofunctional scaffolds for vascular tissue engineering. Scanning electron microscopy images revealed that the RGD-GO-PLGA nanofiber mats were readily fabricated and composed of random-oriented electrospun nanofibers with average diameter of 558 nm. The successful co-functionalization of RGD peptide and GO into the PLGA nanofibers was confirmed by Fourier-transform infrared spectroscopic analysis. Moreover, the surface hydrophilicity of the nanofiber mats was markedly increased by co-functionalizing with RGD peptide and GO. It was found that the mats were thermally stable under the cell culture condition. Furthermore, the initial attachment and proliferation of primarily cultured vascular smooth muscle cells (VSMCs) on the RGD-GO-PLGA nanofiber mats were evaluated. It was revealed that the RGD-GO-PLGA nanofiber mats can effectively promote the growth of VSMCs. In conclusion, our findings suggest that the RGD-GO-PLGA nanofiber mats can be promising candidates for tissue engineering scaffolds effective for the regeneration of vascular smooth muscle. 10.1093/rb/rbx001
    In vivo evaluation of the combination effect of near-infrared laser and 5-fluorouracil-loaded PLGA-coated magnetite nanographene oxide. Mohammadi Gazestani Arezoo,Khoei Samideh,Khoee Sepideh,Emamgholizadeh Minaei Soraya,Motevalian Manijeh Artificial cells, nanomedicine, and biotechnology Magnetite nanographene oxide has exhibited great potential in drug delivery and photothermal therapy (PTT) for cancer treatment. Here we developed 5-fluorouracil-loaded poly (lactic-co-glycolic acid)-coated magnetite nanographene oxide (NGO-SPION-PLGA-5-Fu) to simplify combined PTT and chemotherapy in one complex. The nanocarrier was synthesized using a modified O/W/O/W multiple emulsion solvent evaporation method and was characterized for size, zeta potential, drug loading, in vitro and in vivo release. In this paper, in vivo suppression effect of PTT and chemotherapy using this synthesized magnetite nanographene oxide was studied. The in vitro release of 5-Fu from nanoparticles showed that 41.36% of the drug was released within 24 h. In vivo release showed that 5-Fu has a sustained release profile and prolonged lifetime in the rabbit plasma. Remarkably, a single injection of NGO-SPION-PLGA-5-Fu and 808 nm near-infrared laser (NIR) irradiation for 3 min effectively suppressed the growth of tumours compared with 5-Fu alone (p < .01). Magnetic resonance imaging (MRI) confirmed that the magnetic nanographene oxide was effectively targeted to the tumour site. Therefore, NGO-SPION-PLGA-5-Fu showed excellent PTT efficacy, magnetic targeting property, and MRI ability, indicating that there is a great potential of NGO-SPION-PLGA-5-Fu for cancer theranostic applications. 10.1080/21691401.2018.1450265
    Ternary Aligned Nanofibers of RGD Peptide-Displaying M13 Bacteriophage/PLGA/Graphene Oxide for Facilitated Myogenesis. Shin Yong Cheol,Kim Chuntae,Song Su-Jin,Jun Seungwon,Kim Chang-Seok,Hong Suck Won,Hyon Suong-Hyu,Han Dong-Wook,Oh Jin-Woo Nanotheranostics Recently, there have been tremendous efforts to develop the biofunctional scaffolds by incorporating various biochemical factors. In the present study, we fabricated poly(lactic--glycolic acid) (PLGA) nanofiber sheets decorated with graphene oxide (GO) and RGD peptide. The decoration of GO and RGD peptide was readily achieved by using RGD peptide-displaying M13 bacteriophage (RGD-M13 phage) and electrospinning. Furthermore, the aligned GO-decorated PLGA/RGD peptide (GO-PLGA/RGD) ternary nanofiber sheets were prepared by magnetic field-assisted electrospinning, and their potentials as bifunctional scaffolds for facilitating myogenesis were explored. We characterized the physicochemical and mechanical properties of the sheets by scanning electron microscopy, Raman spectroscopy, contact angle measurement, and tensile test. In addition, the C2C12 skeletal myoblasts were cultured on the aligned GO-PLGA/RGD nanofiber sheets, and their cellular behaviors, including initial attachment, proliferation and myogenic differentiation, were evaluated. Our results revealed that the GO-PLGA/RGD nanofiber sheets had suitable physicochemical and mechanical properties for supporting cell growth, and could significantly promote the spontaneous myogenic differentiation of C2C12 skeletal myoblasts. Moreover, it was revealed that the myogenic differentiation was further accelerated on the aligned GO-PLGA/RGD nanofiber sheets due to the synergistic effects of RGD peptide, GO and aligned nanofiber structure. Therefore, , it is suggested that the aligned GO-PLGA/RGD ternary nanofiber sheets are one of the most promising approaches for facilitating myogenesis and promoting skeletal tissue regeneration. 10.7150/ntno.22433
    Hyaluronic acid and its derivatives in drug delivery and imaging: Recent advances and challenges. Tripodo Giuseppe,Trapani Adriana,Torre Maria Luisa,Giammona Gaetano,Trapani Giuseppe,Mandracchia Delia European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V Hyaluronic acid (HA) is a biodegradable, biocompatible, nontoxic, and non-immunogenic glycosaminoglycan used for various biomedical applications. The interaction of HA with the CD44 receptor, whose expression is elevated on the surface of many types of tumor cells, makes this polymer a promising candidate for intracellular delivery of imaging and anticancer agents exploiting a receptor-mediated active targeting strategy. Therefore, HA and its derivatives have been most investigated for the development of several carrier systems intended for cancer diagnosis and therapy. Nonetheless, different and important delivery applications of the polysaccharide have also been described, including gene and peptide/protein drugs delivery. The aim of this review was to provide an overview of the existing recent literature on the use of HA and its derivatives for drug delivery and imaging. Notable attention is given to nanotheranostic systems obtained after conjugation of HA to nanocarriers as quantum dots, carbon nanotubes and graphene. Meanwhile, attention is also paid to some challenging aspects that need to be addressed in order to allow translation of preclinical models based on HA and its derivatives for drug delivery and imaging purposes to clinical testing and further their development. 10.1016/j.ejpb.2015.03.032
    Enhanced Osteogenic Differentiation of Human Fetal Cartilage Rudiment Cells on Graphene Oxide-PLGA Hybrid Microparticles. Thickett Stuart C,Hamilton Ella,Yogeswaran Gokulan,Zetterlund Per B,Farrugia Brooke L,Lord Megan S Journal of functional biomaterials Poly(d,l-lactide-co-glycolide) (PLGA) has been extensively explored for bone regeneration applications; however, its clinical use is limited by low osteointegration. Therefore, approaches that incorporate osteoconductive molecules are of great interest. Graphene oxide (GO) is gaining popularity for biomedical applications due to its ability to bind biological molecules and present them for enhanced bioactivity. This study reports the preparation of PLGA microparticles via Pickering emulsification using GO as the sole surfactant, which resulted in hybrid microparticles in the size range of 1.1 to 2.4 µm based on the ratio of GO to PLGA in the reaction. Furthermore, this study demonstrated that the hybrid GO-PLGA microparticles were not cytotoxic to either primary human fetal cartilage rudiment cells or the human osteoblast-like cell line, Saos-2. Additionally, the GO-PLGA microparticles promoted the osteogenic differentiation of the human fetal cartilage rudiment cells in the absence of exogenous growth factors to a greater extent than PLGA alone. These findings demonstrate that GO-PLGA microparticles are cytocompatible, osteoinductive and have potential as substrates for bone tissue engineering. 10.3390/jfb10030033
    Correlative ex situ and Liquid-Cell TEM Observation of Bacterial Cell Membrane Damage Induced by Rough Surface Topology. Banner David J,Firlar Emre,Jakubonis Justas,Baggia Yusuf,Osborn Jodi K,Shahbazian-Yassar Reza,Megaridis Constantine M,Shokuhfar Tolou International journal of nanomedicine Background:Nanoscale surface roughness has been suggested to have antibacterial and antifouling properties. Several existing models have attempted to explain the antibacterial mechanism of nanoscale rough surfaces without direct observation. Here, conventional and liquid-cell TEM are implemented to observe nanoscale bacteria/surface roughness interaction. The visualization of such interactions enables the inference of possible antibacterial mechanisms. Methods and Results:Nanotextures are synthesized on biocompatible polymer microparticles (MPs) via plasma etching. Both conventional and liquid-phase transmission electron microscopy observations suggest that these MPs may cause cell lysis via bacterial binding to a single protrusion of the nanotexture. The bacterium/protrusion interaction locally compromises the cell wall, thus causing bacterial death. This study suggests that local mechanical damage and leakage of the cytosol kill the bacteria first, with subsequent degradation of the cell envelope. Conclusion:Nanoscale surface roughness may act via a penetrative bactericidal mechanism. This insight suggests that future research may focus on optimizing bacterial binding to individual nanoscale projections in addition to stretching bacteria between nanopillars. Further, antibacterial nanotextures may find use in novel applications employing particles in addition to nanotextures on fibers or films. 10.2147/IJN.S232230
    A novel nanostructured poly(lactic-co-glycolic-acid)-multi-walled carbon nanotube composite for blood-contacting applications: thrombogenicity studies. Koh Li Buay,Rodriguez Isabel,Venkatraman Subbu S Acta biomaterialia Composite films of poly(lactic-co-glycolic-acid) with multi-walled carbon nanotubes (PLGA-MWCNT) having two different nanotube orientations, namely random and vertically aligned, have been fabricated and characterized. The effect of these nanostructured surfaces on platelet adhesion is evaluated. In particular, the thrombogenicity of the nanostructured composite films is compared with that of pristine graphite (a low thrombogenic material) and PLGA film, in order to determine the influence of surface chemistry and topography on platelet adhesion. The results in this study show that the PLGA-MWCNT composite with vertically aligned nanotubes exhibits very low levels of fibrinogen adsorption and platelet adhesion, which can be attributed to both chemical and topographical effects. Platelet adhesion shows a good correlation with the presence of COOH groups and appears to be sensitive to the topographic features of the composite films. The results in this study suggest that in addition to chemistry, nanotopographical surface modifications could be an effective strategy in the development of low thrombogenic and hemocompatible materials. 10.1016/j.actbio.2009.06.003
    Evaluation of the combined effect of NIR laser and ionizing radiation on cellular damages induced by IUdR-loaded PLGA-coated Nano-graphene oxide. Kargar Samira,Khoei Samideh,Khoee Sepideh,Shirvalilou Sakine,Mahdavi Seied Rabi Photodiagnosis and photodynamic therapy Glioma is one of the most common malignant cancers of the central nervous system (CNS). Radiatherapy and chemotherapy may be used to slow the growth of tumors that cannot be removed with surgery. The current study developed a combination therapy tool using Nanographene oxide (NGO) functionalized with poly lactic-co-glycolic acid (PLGA) as a carrier of 5-iodo-2-deoxyuridine (IUdR) for glioma cancer treatment. U87MG cells were treated in different groups with IUdR, PLGA-coated Nanographene oxide (PLGA-NGO), IUdR-loaded PLGA-coated Nanographene oxide (IUdR-PLGA-NGO), 2Gy 6MV X-ray radiation, and near-infrared region (NIR) laser radiation. PLGA-NGO showed excellent biocompatibility, high storage capacity for IUdR and high photothermal conversion efficiency. It was effectively employed to create cell damage in the U87MG cell line in the presence of X-ray (6 MV) and NIR laser. Moreover, IUdR-PLGA-NGO+X-ray+NIR laser significantly reduced the plating efficiency of the cells in comparison with IUdR-PLGA-NGO+X-ray and IUdR-PLGA-NGO+NIR laser. Furthermore, Prussian blue staining showed that IUdR-PLGA-NGO-SPIONs were delivered into glioblastoma cells. The PLGA-NGO loaded with IUdR under NIR and X-ray radiation exhibited the highest cytotoxicity toward U87MG cells when compared with other treatment methods, indicating efficient radio-photothermal targeted therapy. 10.1016/j.pdpdt.2017.11.007
    Plasmonic carbon nanohybrids for repetitive and highly localized photothermal cancer therapy. Chauhan Deepak S,Kumawat Mukesh K,Prasad Rajendra,Reddy Pradeep K,Dhanka Mukesh,Mishra Sumit K,Bahadur Rohan,Neekhra Suditi,De Abhijit,Srivastava Rohit Colloids and surfaces. B, Biointerfaces Integrating metallic and non-metallic platform for cancer nanomedicine is a challenging task and bringing together multi-functionality of two interfaces is a major hurdle for biomaterial design. Herein, NIR light responsive advanced hybrid plasmonic carbon nanomaterials are synthesized, and their properties toward repetitive and highly localized photothermal cancer therapy are well understood. Graphene oxide nanosheets having thickness of ∼2 nm are synthesized using modified Hummers' method, thereafter functionalized with biodegradable NIR light responsive gold deposited plasmonic polylactic-co-glycolic acid nanoshells (AuPLGA NS, tuned at 808 nm) and NIR dye (IR780) to examine their repetitive and localized therapeutic efficacy as well resulting side effects to nearby healthy cells. It is observed that AuPLGA NS decorated graphene oxide nanosheets (GO-AuPLGA) and IR780 loaded graphene oxide nanosheets (GO-IR780) are capable in standalone complete photothermal ablation of cancer cells within 4 min. of 808 nm NIR laser irradiation and also without the aid of any anticancer drugs. However, GO-AuPLGA having the potential for repetitive photothermal treatment of a big tumor, ablate the cancer cells in highly localized fashion, without having side effects on neighboring healthy cells. 10.1016/j.colsurfb.2018.08.054
    3D-printing porosity: A new approach to creating elevated porosity materials and structures. Jakus A E,Geisendorfer N R,Lewis P L,Shah R N Acta biomaterialia We introduce a new process that enables the ability to 3D-print high porosity materials and structures by combining the newly introduced 3D-Painting process with traditional salt-leaching. The synthesis and resulting properties of three 3D-printable inks comprised of varying volume ratios (25:75, 50:50, 70:30) of CuSO salt and polylactide-co-glycolide (PLGA), as well as their as-printed and salt-leached counterparts, are discussed. The resulting materials are comprised entirely of PLGA (F-PLGA), but exhibit porosities proportional to the original CuSO content. The three distinct F-PLGA materials exhibit average porosities of 66.6-94.4%, elastic moduli of 112.6-2.7 MPa, and absorbency of 195.7-742.2%. Studies with adult human mesenchymal stem cells (hMSCs) demonstrated that elevated porosity substantially promotes cell adhesion, viability, and proliferation. F-PLGA can also act as carriers for weak, naturally or synthetically-derived hydrogels. Finally, we show that this process can be extended to other materials including graphene, metals, and ceramics. STATEMENT OF SIGNIFICANCE:Porosity plays an essential role in the performance and function of biomaterials, tissue engineering, and clinical medicine. For the same material chemistry, the level of porosity can dictate if it is cell, tissue, or organ friendly; with low porosity materials being far less favorable than high porosity materials. Despite its importance, it has been difficult to create three-dimensionally printed structures that are comprised of materials that have extremely high levels of internal porosity yet are surgically friendly (able to handle and utilize during surgical operations). In this work, we extend a new materials-centric approach to 3D-printing, 3D-Painting, to 3D-printing structures made almost entirely out of water-soluble salt. The structures are then washed in a specific way that not only extracts the salt but causes the structures to increase in size. With the salt removed, the resulting medical polymer structures are almost entirely porous and contain very little solid material, but the maintain their 3D-printed form and are highly compatible with adult human stem cells, are mechanically robust enough to use in surgical manipulations, and can be filled with and act as carriers for biologically active liquids and gels. We can also extend this process to three-dimensionally printing other porous materials, such as graphene, metals, and even ceramics. 10.1016/j.actbio.2018.03.039
    Biological and mechanical evaluation of poly(lactic-co-glycolic acid)-based composites reinforced with 1D, 2D and 3D carbon biomaterials for bone tissue regeneration. Kaur Tejinder,Kulanthaivel Senthilguru,Thirugnanam Arunachalam,Banerjee Indranil,Pramanik Krishna Biomedical materials (Bristol, England) Considering the fact that life on Earth is carbon based, carbon materials are being introduced in biological systems. However, very limited information exists concerning the potential effects of different structures of carbon materials on biological systems. In the present study, poly(lactic-co-glycolic acid) (PLGA)-based carbonaceous composites were developed by reinforcing 1 wt% of three different carbon-based materials i.e. carbon nanotubes (CNTs-1D), graphene nanoplatelets (GNPs-2D), and activated carbon (AC-3D). The developed composites were characterized for physicochemical, biological, and mechanical properties. Along with their hemocompatible nature, the composites exhibited better swelling ratio, degradation percentage, bioactivity, and tensile strength. The improvement in hydrophilicity and protein adsorption resulted in the enhancement of cell proliferation and differentiation. Overall, sheet-like GNPs showed the strongest effect on the composite's properties due to their larger exposed area. These results demonstrate the potential of PLGA-based carbonaceous composites for accelerating bone tissue regeneration. 10.1088/1748-605X/aa5f76
    Enhanced bone formation in electrospun poly(L-lactic-co-glycolic acid)-tussah silk fibroin ultrafine nanofiber scaffolds incorporated with graphene oxide. Shao Weili,He Jianxin,Sang Feng,Wang Qian,Chen Li,Cui Shizhong,Ding Bin Materials science & engineering. C, Materials for biological applications To engineer bone tissue, it is necessary to provide a biocompatible, mechanically robust scaffold. In this study, we fabricated an ultrafine nanofiber scaffold by electrospinning a blend of poly(L-lactic-co-glycolic acid), tussah silk fibroin, and graphene oxide (GO) and characterized its morphology, biocompatibility, mechanical properties, and biological activity. The data indicate that incorporation of 10 wt.% tussah silk and 1 wt.% graphene oxide into poly(L-lactic-co-glycolic acid) nanofibers significantly decreased the fiber diameter from 280 to 130 nm. Furthermore, tussah silk and graphene oxide boosted the Young's modulus and tensile strength by nearly 4-fold and 3-fold, respectively, and significantly enhanced adhesion, proliferation in mouse mesenchymal stem cells and functionally promoted biomineralization-relevant alkaline phosphatase (ALP) and mineral deposition. The results indicate that composite nanofibers could be excellent and versatile scaffolds for bone tissue engineering. 10.1016/j.msec.2016.01.078
    Enhanced proliferation and osteogenic differentiation of mesenchymal stem cells on graphene oxide-incorporated electrospun poly(lactic-co-glycolic acid) nanofibrous mats. Luo Yu,Shen He,Fang Yongxiang,Cao Yuhua,Huang Jie,Zhang Mengxin,Dai Jianwu,Shi Xiangyang,Zhang Zhijun ACS applied materials & interfaces Currently, combining biomaterial scaffolds with living stem cells for tissue regeneration is a main approach for tissue engineering. Mesenchymal stem cells (MSCs) are promising candidates for musculoskeletal tissue repair through differentiating into specific tissues, such as bone, muscle, and cartilage. Thus, successfully directing the fate of MSCs through factors and inducers would improve regeneration efficiency. Here, we report the fabrication of graphene oxide (GO)-doped poly(lactic-co-glycolic acid) (PLGA) nanofiber scaffolds via electrospinning technique for the enhancement of osteogenic differentiation of MSCs. GO-PLGA nanofibrous mats with three-dimensional porous structure and smooth surface can be readily produced via an electrospinning technique. GO plays two roles in the nanofibrous mats: first, it enhances the hydrophilic performance, and protein- and inducer-adsorption ability of the nanofibers. Second, the incorporated GO accelerates the human MSCs (hMSCs) adhesion and proliferation versus pure PLGA nanofiber and induces the osteogenic differentiation. The incorporating GO scaffold materials may find applications in tissue engineering and other fields. 10.1021/acsami.5b00862
    Coating of ß-tricalcium phosphate scaffolds-a comparison between graphene oxide and poly-lactic-co-glycolic acid. Ardjomandi N,Henrich A,Huth J,Klein C,Schweizer E,Scheideler L,Rupp F,Reinert S,Alexander D Biomedical materials (Bristol, England) Bone regeneration in critical size defects is a major challenge in oral and maxillofacial surgery, and the gold standard for bone reconstruction still requires the use of autologous tissue. To overcome the need for a second intervention and to minimize morbidity, the development of new biomaterials with osteoinductive features is the focus of current research. As a scaffolding material, ß-tricalcium phosphate (ß-TCP) is suitable for bone regeneration purposes, although it does not carry any functional groups for the covalent immobilization of molecules. The aim of the present study was to establish effective coating variants for ß-TCP constructs to enable the biofunctionalization of anorganic blocks with different osteogenic molecules in future studies. We established working protocols for thin surface coatings consisting of polylactic-co-glycolic acid (PLGA) and graphene oxide (GO) by varying parameters. Surface properties such as the angularity and topography of the developed scaffolds were analyzed. To examine biological functionality, the adhesion and proliferation behavior of jaw periosteal cells (JPCs) were tested on the coated constructs. Our results suggest that PLGA is the superior material for surface coating of ß-TCP matrices, leading to higher JPC proliferation rates and providing a more suitable basis for further biofunctionalization in the field of bone tissue engineering. 10.1088/1748-6041/10/4/045018
    Photoacoustic stimulation promotes the osteogenic differentiation of bone mesenchymal stem cells to enhance the repair of bone defect. Huang Zebin,Xu Jiankun,Chen Jiebin,Chen Hongjiang,Wang Hailong,Huang Zhonglian,Chen Youbin,Lu Xiaolin,Lu Fushen,Hu Jun Scientific reports The aim of this study was to evaluate the direct photoacoustic (PA) effect on bone marrow mesenchymal stem cells (BMSCs) which is a key cell source for osteogenesis. As scaffold is also an indispensable element for tissue regeneration, here we firstly fabricated a composited sheet using polylactic-co-glycolic acid (PLGA) mixing with graphene oxide (GO). BMSCs were seeded on the PLGA-GO sheets and received PA treatment in vitro for 3, 9 and 15 days, respectively. Then the BMSCs were harvested and subjected to assess alkaline phosphatase (ALP) activity, calcium content and osteopontin (OPN) on 3, 9 and 15 days. For in vivo study, PLGA-GO sheet seeded with BMSCs after in vitro PA stimulation for 9 days were implanted to repair the bone defect established in the femoral mid-shaft of Sprague-Dawley rat. PLGA-GO group with PA pretreatment showed promising outcomes in terms of the expression of ALP, OPN, and calcium content, thus enhanced the repair of bone defect. In conclusion, we have developed an alternative approach to enhance the repair of bone defect by making good use of the beneficial effect of PA. 10.1038/s41598-017-15879-4
    Polyethylene glycol-functionalized poly (Lactic Acid-co-Glycolic Acid) and graphene oxide nanoparticles induce pro-inflammatory and apoptotic responses in Candida albicans-infected vaginal epithelial cells. Wagner R Doug,Johnson Shemedia J,Danielsen Zhixia Yan,Lim Jin-Hee,Mudalige Thilak,Linder Sean PloS one Mucous-penetrating nanoparticles consisting of poly lactic acid-co-glycolic acid (PLGA)-polyethylene glycol (PEG) could improve targeting of microbicidal drugs for sexually transmitted diseases by intravaginal inoculation. Nanoparticles can induce inflammatory responses, which may exacerbate the inflammation that occurs in the vaginal tracts of women with yeast infections. This study evaluated the effects of these drug-delivery nanoparticles on VK2(E6/E7) vaginal epithelial cell proinflammatory responses to Candida albicans yeast infections. Vaginal epithelial cell monolayers were infected with C. albicans and exposed to 100 μg/ml 49.5 nm PLGA-PEG nanospheres or 20 μg/ml 1.1 x 500 nm PEG-functionalized graphene oxide (GO-PEG) sheets. The cells were assessed for changes in mRNA and protein expression of inflammation-related genes by RT-qPCR and physiological markers of cell stress using high content analysis and flow cytometry. C. albicans exposure suppressed apoptotic gene expression, but induced oxidative stress in the cells. The nanomaterials induced cytotoxicity and programmed cell death responses alone and with C. albicans. PLGA-PEG nanoparticles induced mRNA expression of apoptosis-related genes and induced poly (ADP-ribose) polymerase (PARP) cleavage, increased BAX/BCL2 ratios, and chromatin condensation indicative of apoptosis. They also induced autophagy, endoplasmic reticulum stress, and DNA damage. They caused the cells to excrete inflammatory recruitment molecules chemokine (C-X-C motif) ligand 1 (CXCL1), interleukin-1α (IL1A), interleukin-1β (IL1B), calprotectin (S100A8), and tumor necrosis factor α (TNF). GO-PEG nanoparticles induced expression of necrosis-related genes and cytotoxicity. They reduced autophagy and endoplasmic reticulum stress, and apoptotic gene expression responses. The results show that stealth nanoparticle drug-delivery vehicles may cause intracellular damage to vaginal epithelial cells by several mechanisms and that their use for intravaginal drug delivery may exacerbate inflammation in active yeast infections by increased inflammatory recruitment. 10.1371/journal.pone.0175250
    Release of methylene blue from graphene oxide-coated electrospun nanofibrous scaffolds to modulate functions of neural progenitor cells. Wang Lina,Liu Xiaoyun,Fu Jiqiang,Ning Xinyu,Zhang Mengxin,Jiang Ziyun,Cheng Guosheng,Zhu Yimin,Zhang Zhijun Acta biomaterialia Transplantation of neural progenitor cells (NPCs) can repair the damaged neurons and therefore holds significant promise as a new treatment strategy for Alzheimer's disease (AD). Development of functional scaffolds for the growth, proliferation, and differentiation of NPCs offers a useful approach for AD therapy. In our study, the functional scaffolds were obtained by fabrication of a poly(lactic-co-glycolic acid) (PLGA) nanofibrous mat by the electrospinning technique, followed by coating of a layer of graphene oxide (GO) and then physisorption of methylene blue (MB) under mild conditions. The precoating of GO on the nanofibrous scaffolds allows efficient loading and release of MB from the substrate for regulating the functions of NPCs. The NPCs cultured on the scaffolds remained in the quiescence phase due to the activation of autophagy signaling pathway by MB. Moreover, the MB-loaded nanofibrous scaffolds diminish tau phosphorylation and protect NPCs from apoptosis. Definitely, more work, especially the in vivo experiment, is highly desired to demonstrate the feasibility of the current strategy for AD treatment. STATEMENT OF SIGNIFICANCE: Transplantation of neural progenitor cells (NPCs) can repair the damaged neurons and hold significant promise as a new treatment strategy for Alzheimer's disease (AD). Development of functional scaffolds for the growth, proliferation, and differentiation of NPCs offers a novel and useful approach for AD therapy. In this work, we have developed a GO and MB sequentially coated PLGA nanofibrous mat as a new scaffold for NPC transplantation and tauopathy inhibition. The coating of GO that we have demonstrated significantly enhanced the loading and release of MB on the scaffolds. Furthermore, NPCs cultured on the nanofibrous scaffolds entered quiescence phase through the activation of autophagy signaling pathway, leading to improved performance of NPCs to cope with stressors of disease. More importantly, the release of MB from the scaffolds leads to attenuation of tauopathy and protection of NPCs, which may represent a novel, versatile, and effective therapeutic approach for AD and other neurodegenerative diseases. 10.1016/j.actbio.2019.02.036
    Effect of electrical stimulation combined with graphene-oxide-based membranes on neural stem cell proliferation and differentiation. Fu Chuan,Pan Su,Ma Yue,Kong Weijian,Qi Zhiping,Yang Xiaoyu Artificial cells, nanomedicine, and biotechnology The combination of composite nerve materials prepared using degradable polymer materials with biological or physical factors has received extensive attention as a means to treat nerve injuries. This study focused on the potential application of graphene oxide (GO) composite conductive materials combined with electrical stimulation (ES) in nerve repair. A conductive poly(L-lactic-co-glycolic acid) (PLGA)/GO composite membrane was prepared, and its properties were tested using a scanning electron microscope (SEM), a contact angle meter, and a mechanical tester. Next, neural stem cells (NSCs) were planted on the PLGA/GO conductive composite membrane and ES was applied. NSC proliferation and differentiation and neurite elongation were observed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, immunofluorescence, and PCR, respectively. The results showed that the PLGA/GO membrane had good hydrophilicity, mechanical strength, and protein adsorption. ES combined with the PLGA/GO membrane significantly promoted NSC proliferation and neuronal differentiation on the material surface and promoted significant neurite elongation. Our results suggest that ES combined with GO-related conductive composite materials can be used as a new therapeutic combination to treat nerve injuries. 10.1080/21691401.2019.1613422
    Stimulated myoblast differentiation on graphene oxide-impregnated PLGA-collagen hybrid fibre matrices. Shin Yong Cheol,Lee Jong Ho,Jin Linhua,Kim Min Jeong,Kim Yong-Joo,Hyun Jung Keun,Jung Tae-Gon,Hong Suck Won,Han Dong-Wook Journal of nanobiotechnology BACKGROUND:Electrospinning is a simple and effective method for fabricating micro- and nanofiber matrices. Electrospun fibre matrices have numerous advantages for use as tissue engineering scaffolds, such as high surface area-to-volume ratio, mass production capability and structural similarity to the natural extracellular matrix (ECM). Therefore, electrospun matrices, which are composed of biocompatible polymers and various biomaterials, have been developed as biomimetic scaffolds for the tissue engineering applications. In particular, graphene oxide (GO) has recently been considered as a novel biomaterial for skeletal muscle regeneration because it can promote the growth and differentiation of myoblasts. Therefore, the aim of the present study was to fabricate the hybrid fibre matrices that stimulate myoblasts differentiation for skeletal muscle regeneration. RESULTS:Hybrid fibre matrices composed of poly(lactic-co-glycolic acid, PLGA) and collagen (Col) impregnated with GO (GO-PLGA-Col) were successfully fabricated using an electrospinning process. Our results indicated that the GO-PLGA-Col hybrid matrices were comprised of randomly-oriented continuous fibres with a three-dimensional non-woven porous structure. Compositional analysis showed that GO was dispersed uniformly throughout the GO-PLGA-Col matrices. In addition, the hydrophilicity of the fabricated matrices was significantly increased by blending with a small amount of Col and GO. The attachment and proliferation of the C2C12 skeletal myoblasts were significantly enhanced on the GO-PLGA-Col hybrid matrices. Furthermore, the GO-PLGA-Col matrices stimulated the myogenic differentiation of C2C12 skeletal myoblasts, which was enhanced further under the culture conditions of the differentiation media. CONCLUSIONS:Taking our findings into consideration, it is suggested that the GO-PLGA-Col hybrid fibre matrices can be exploited as potential biomimetic scaffolds for skeletal tissue engineering and regeneration because these GO-impregnated hybrid matrices have potent effects on the induction of spontaneous myogenesis and exhibit superior bioactivity and biocompatibility. 10.1186/s12951-015-0081-9
    Graphene Oxide Incorporated PLGA Nanofibrous Scaffold for Solid Phase Gene Delivery into Mesenchymal Stem Cells. Wang Zhiying,Shen He,Song Saijie,Zhang Liming,Chen Wei,Dai Jianwu,Zhang Zhijun Journal of nanoscience and nanotechnology Delivery of functional genes into stem cells shows great application prospect in DNA-based tissue engineering. However, comparing with epithelial cells and cancer cells, stem cells usually exhibit low gene transfection efficiency. To enhance the transfection efficiency, non-viral gene delivery in combination with biomaterial scaffolds, has raised increasing interests from researchers in tissue engineering. Nanofibers fabricated by electrospinning technique mimicking extracellular matrix (ECM) are widely used in tissue engineering applications. In addition, graphene oxide (GO) with ultrahigh specific surface area and ultra-strong adsorption capability, is an ideal candidate for gene delivery. In this work, polyethylenimine (PEI)/plasmid DNA-GO/poly(D,L-lactic-co-glycolic acid) (PLGA) scaffold was developed as a substrate for solid phase gene delivery and a tissue engineering substrate for stem cells growth and differentiation. In order to improve the transfection efficiency of stem cells, PEI/pDNA complexes were immobilized at the surface of electropun GO incorporated PLGA nanofibrous mat. Human embryonic kidney 293 cells and human umbilical cord derived mesenchymal stem cells cultured on PEI/pDNA-GO/PLGA scaffold showed significantly higher green fluorescent protein (GFP) expression than PEI/pGFP in the medium. These findings demonstrated that solid phase gene delivery using PEI/pDNA-GO/PLGA significantly enhanced the gene transfection efficiency, and may find potential application of gene therapy and regeneration medicine. 10.1166/jnn.2018.14362
    Promoting tendon to bone integration using graphene oxide-doped electrospun poly(lactic-co-glycolic acid) nanofibrous membrane. Su Wei,Wang Zhiying,Jiang Jia,Liu Xiaoyun,Zhao Jinzhong,Zhang Zhijun International journal of nanomedicine Background:These normal entheses are not reestablished after repair despite significant advances in surgical techniques. There is a significant need to develop integrative biomaterials, facilitating functional tendon-to-bone integration. Materials and methods:We fabricated a highly interconnective graphene oxide-doped electrospun poly(lactide-co-glycolide acid) (GO-PLGA) nanofibrous membrane by electrospinning technique and evaluated them using in vitro cell assays. Then, we established rabbit models, the PLGA and GO-PLGA nanofibrous membranes were used to augment the rotator cuff repairs. The animals were killed postoperatively, which was followed by micro-computed tomography, histological and biomechanical evaluation. Results:GO was easily mixed into PLGA filament without changing the three dimensional microstructure. An in vitro evaluation demonstrated that the PLGA membranes incorporated with GO accelerated the proliferation of BMSCs and furthered the Osteogenic differentiation of BMSCs. In addition, an in vivo assessment further revealed that the local application of GO-PLGA membrane to the gap between the tendon and the bone in a rabbit model promoted the healing enthesis, increased new bone and cartilage generation, and improved collagen arrangement and biomechanical properties in comparison with repair with PLGA only. Conclusion:The electrospun GO-PLGA fibrous membrane provides an effective approach for the regeneration of tendon to bone enthesis. 10.2147/IJN.S183842
    Development of a magnetic nano-graphene oxide carrier for improved glioma-targeted drug delivery and imaging: In vitro and in vivo evaluations. Shirvalilou Sakine,Khoei Samideh,Khoee Sepideh,Raoufi Nida Jamali,Karimi Mohammad Reza,Shakeri-Zadeh Ali Chemico-biological interactions To overcome the obstacles inflicted by the BBB in Glioblastoma multiforme (GBM) we investigated the use of Multifunctional nanoparticles that designed with a Nano-graphene oxide (NGO) sheet functionalized with magnetic poly (lactic-co-glycolic acid) (PLGA) and was used for glioma targeting delivery of radiosensitizing 5-iodo-2-deoxyuridine (IUdR). In vitro biocompatibility of nanocomposite has been studied by the MTT assay. In vivo efficacy of magnetic targeting on the amount and selectivity of magnetic nanoparticles accumulation in glioma-bearing rats under an external magnetic field (EMF) density of 0.5 T was easily monitored with MRI. IUdR-loaded magnetic NGO/PLGA with a diameter of 71.8 nm, a zeta potential of -33.07 ± 0.07 mV, and a drug loading content of 3.04 ± 0.46% presented superior superparamagnetic properties with a saturation magnetization (Ms) of 15.98 emu/g. Furthermore, Prussian blue staining showed effective magnetic targeting, leading to remarkably improved tumor inhibitory efficiency of IUdR. The tumor volume of rats after treatment with IUdR/NGO/SPION/PLGA + MF was decreased significantly compared to the rats treated with buffer saline, IUdR and SPION/IUdR/NGO/PLGA. Most importantly, our data demonstrate that IUdR/NGO/SPION/PLGA at the present magnetic field prolongs the median survival time of animals bearing gliomas (38 days, p < 0.01). Nanoparticles also had high thermal sensitivities under the alternating magnetic field. In conclusion, we developed magnetic IUdR/NGO/PLGA, which not only achieved to high accumulation at the targeted tumor site by magnetic targeting but also indicated significantly enhanced therapeutic efficiency and toxicity for glioma both in vitro and in vivo. This innovation increases the possibility of improving clinical efficiency of IUdR as a radiosensitizer, or lowering the total drug dose to decrease systemic toxicity. 10.1016/j.cbi.2018.08.027
    Poly (lactic-co-glycolic acid)/graphene oxide composites combined with electrical stimulation in wound healing: preparation and characterization. You Di,Li Kai,Guo Wenlai,Zhao Guoqing,Fu Chuan International journal of nanomedicine Purpose:In this study, we fabricated multifunctional, electrically conductive composites by incorporating graphene oxide (GO) into a poly (lactic-co-glycolic acid) (PLGA) copolymer for wound repair. Furthermore, the resultant composites were coupled with electrical stimulation to further improve the therapeutic effect of wound repair. Methods:We evaluated the surface morphology of the composites, as well as their physical properties, cytotoxicity, and antibacterial activity, along with the combined effects of composites and electrical stimulation (ES) in a rat model of wound healing. Results:Application of the PLGA/GO composites to full-thickness wounds confirmed their advantageous biological properties, as evident from the observed improvements in wound-specific mechanical properties, biocompatibility, and antibacterial activity. Additionally, we found that the combination of composites and ES improved composite-mediated cell survival and accelerated wound healing in vivo by promoting neovascularization and the formation of type I collagen. Conclusion:These results demonstrated that combined treatment with the PLGA/GO composite and ES promoted vascularization and epidermal remodeling and accelerated wound healing in rats, thereby suggesting the efficacy of PLGA/GO+ES for broad applications associated with wound repair. 10.2147/IJN.S216365
    Porous PLGA microspheres tailored for dual delivery of biomolecules via layer-by-layer assembly. Go Dewi P,Palmer Jason A,Mitchell Geraldine M,Gras Sally L,O'Connor Andrea J Journal of biomedical materials research. Part A Tissue engineering is a complex and dynamic process that requires varied biomolecular cues to promote optimal tissue growth. Consequently, the development of delivery systems capable of sequestering more than one biomolecule with controllable release profiles is a key step in the advancement of this field. This study develops multilayered polyelectrolyte films incorporating alpha-melanocyte stimulating hormone (α-MSH), an anti-inflammatory molecule, and basic fibroblast growth factor (bFGF). The layers were successfully formed on macroporous poly lactic-co-glycolic acid microspheres produced using a combined inkjet and thermally induced phase separation technique. Release profiles could be varied by altering layer properties including the number of layers and concentrations of layering molecules. α-MSH and bFGF were released in a sustained manner and the bioactivity of α-MSH was shown to be preserved using an activated macrophage cell assay in vitro. The system performance was also tested in vivo subcutaneously in rats. The multilayered microspheres reduced the inflammatory response induced by a carrageenan stimulus 6 weeks after implantation compared to the non-layered microspheres without the anti-inflammatory and growth factors, demonstrating the potential of such multilayered constructs for the controlled delivery of bioactive molecules. 10.1002/jbm.a.35319
    Antimicrobial Activity of 3D-Printed Poly(ε-Caprolactone) (PCL) Composite Scaffolds Presenting Vancomycin-Loaded Polylactic Acid-Glycolic Acid (PLGA) Microspheres. Zhou Zhi,Yao Qingqiang,Li Lan,Zhang Xin,Wei Bo,Yuan Li,Wang Liming Medical science monitor : international medical journal of experimental and clinical research BACKGROUND The aim of this study was to design and test a novel composite scaffold with antibacterial efficacy for treating bone infections using a three-dimensional (3D) printed poly(ε-caprolactone) (PCL) scaffold coated with polydopamine (PDA) for the adsorption of polylactic acid-glycolic acid (PLGA) microspheres loaded with vancomycin. MATERIAL AND METHODS Vancomycin-loaded PLGA microspheres were produced by the double-emulsion method, and microsphere morphology, drug-loading dosage, encapsulation efficiency, average diameter, and release characteristics were examined. Composite scaffolds were prepared by adsorption of the microspheres on PDA-coated, 3D-printed PCL scaffolds, and scaffold morphology, biocompatibility, vancomycin release, and antibacterial efficacy were evaluated. RESULTS The vancomycin-loaded microspheres were smooth, round, uniform in size, and had no adhesion phenomenon, and exhibited sustained release of vancomycin from the microspheres for more than 4 weeks. Upon modification with PDA, the PCL scaffold changed from white to black, and after microsphere adsorption, dot-like white particles were seen. On scanning electron microscopy, PDA particles were observed on the PCL/PDA composite scaffolds, and PLGA microspheres were evenly dispersed over the PDA coating on the PCL/PDA/PLGA composite scaffolds. Cell viability assays showed that the adhesion and proliferation of rabbit bone mesenchymal stem cells were greater on the PCL/PDA scaffolds than on unmodified PCL scaffolds. Microsphere adsorption had no significant effect on cell proliferation. In vitro release of vancomycin from the composite scaffolds was observed for more than 4 weeks, and observation of the inhibition zone on agar plates of Staphylococcus aureus showed that the scaffolds maintained their antibacterial effect for more than 4 weeks. CONCLUSIONS The 3D-printed, PDA-coated PCL scaffold carrying vancomycin-loaded PLGA microspheres exhibited good biocompatibility and a sustained antibacterial effect in vitro. 10.12659/MSM.911770
    Characterization of attributes and in vitro performance of exenatide-loaded PLGA long-acting release microspheres. Li Tinghui,Chandrashekar Aishwarya,Beig Avital,Walker Jennifer,Hong Justin K Y,Benet Alexander,Kang Jukyung,Ackermann Rose,Wang Yan,Qin Bin,Schwendeman Anna S,Schwendeman Steven P European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V Bydureon® (Bdn) is a once-weekly injectable long-acting release (LAR) product for adults with type 2 diabetes based on PLGA microspheres encapsulating the glucagon like peptide (GLP-1) analog, exenatide. Despite its widespread use in type 2 diabetes treatment, little information has been published concerning the physical-chemical aspects and exenatide stability in this product. Here, we developed and validated methods to evaluate attributes and performance of Bdn such as particle size/size distribution and residual levels of moisture and organic solvent(s). The reverse engineering of the exenatide LAR was also performed to identify and quantify principal components in the product. Stability-indicating UPLC and LC-MS methods were applied to characterize exenatide degradation (such as oxidation, deamidation and acylation products) during in vitro release evaluation. The 55-μm volume-median Bdn microspheres slowly released the exenatidein vitroover two months with a very low initial burst release to avoid unwanted side effects. Residual organic solvent levels (methylene chloride, ethanol, heptane, and silicon oil) also met the USP criteria. Peptide acylation was the most prominent peptide reaction during both encapsulation and in vitro release, and the acylated peptide steadily increased during release relative to parent exenatide, becoming the most abundant peptide species extracted from the microspheres at later release stages. The presence of peptide impurities during the release period, which are not extractable in the polymer and likely insoluble in water, might be one potential cause for immunogenicity. Further evaluation will be needed to confirm this hypothesis. Release of peptide was minimal over the first 2 weeks before the microspheres steadily released peptide for more than 28 days. The rigorous technical approach discussed in this paper may provide critical information for both companies and the FDA for developing generic exenatide-PLGA formulations and other important PLGA microsphere products. 10.1016/j.ejpb.2020.10.008
    Enhanced cell proliferation and osteogenic differentiation in electrospun PLGA/hydroxyapatite nanofibre scaffolds incorporated with graphene oxide. Fu Chuan,Bai Haotian,Zhu Jiaqi,Niu Zhihao,Wang Yu,Li Jianan,Yang Xiaoyu,Bai Yunshen PloS one One of the goals of bone tissue engineering is to mimic native ECM in architecture and function, creating scaffolds with excellent biocompatibility, osteoinductive ability and mechanical properties. The aim of this study was to fabricate nanofibrous matrices by electrospinning a blend of poly (L-lactic-co-glycolic acid) (PLGA), hydroxyapatite (HA), and grapheme oxide (GO) as a favourable platform for bone tissue engineering. The morphology, biocompatibility, mechanical properties, and biological activity of all nanofibrous matrices were compared. The data indicate that the hydrophilicity and protein adsorption rate of the fabricated matrices were significantly increased by blending with a small amount of HA and GO. Furthermore, GO significantly boosted the tensile strength of the nanofibrous matrices, and the PLGA/GO/HA nanofibrous matrices can serve as mechanically stable scaffolds for cell growth. For further test in vitro, MC3T3-E1 cells were cultured on the PLGA/HA/GO nanofbrous matrices to observe various cellular activities and cell mineralization. The results indicated that the PLGA/GO/HA nanofibrous matrices significantly enhanced adhesion, and proliferation in MCET3-E1 cells and functionally promoted alkaline phosphatase (ALP) activity, the osteogenesis-related gene expression and mineral deposition. Therefore, the PLGA/HA/GO composite nanofibres are excellent and versatile scaffolds for applications in bone tissue regeneration. 10.1371/journal.pone.0188352
    Fabrication of silk fibroin/poly(lactic-co-glycolic acid)/graphene oxide microfiber mat via electrospinning for protective fabric. Liu Zulan,Shang Songmin,Chiu Ka-Lok,Jiang Shouxiang,Dai Fangyin Materials science & engineering. C, Materials for biological applications In this study, a biodegradable silk fibroin/poly(lactic-co-glycolic acid)/graphene oxide (SF/PLGA/GO) microfiber mat was successfully fabricated via electrospinning for use in protective fabrics. The morphology of the microfiber mat was characterized by Scanning Electron Microscope (SEM). The thermal and mechanical properties, water contact angle, surface area and pore size of the microfiber mats were characterized. Due to the introduction of graphene which can interact with silk fibroin, the SF/PLGA/GO microfiber mat, compared with the silk fibroin/poly (lactic-co-glycolic acid) (SF/PLGA) microfiber mat, has higher strength, greater Young's modulus and better thermal stability which can meet the requirements of protective fabric. The microfiber mat is biodegradable because its main component is silk fibroin and PLGA. In particular, the microfiber mat has a small pore size range of 4 ∼ 10 nm in diameter, a larger surface area of 2.63 m g and pore volume of 7.09 × 10 cm g. The small pore size of the mat can effectively block the particulate pollutants and pathogenic particles in the air. The larger surface area and pore volume of the mat are effective for breathability. Therefore, the fabricated SF/PLGA/GO microfiber mat has great application potentials for protective fabrics. 10.1016/j.msec.2019.110308
    Enhancement radiation-induced apoptosis in C6 glioma tumor-bearing rats via pH-responsive magnetic graphene oxide nanocarrier. Shirvalilou Sakine,Khoei Samideh,Khoee Sepideh,Mahdavi Seied Rabi,Raoufi Nida Jamali,Motevalian Manijeh,Karimi Mohammad Yahya Journal of photochemistry and photobiology. B, Biology 5-iodo-2-deoxyuridine (IUdR) has been demonstrated to induce an appreciable radiosensitizing effect on glioblastoma patients, but due to the short circulation half-life times and failure to pass through the blood-brain barrier (BBB), its clinical use is limited. Accordingly, in this study, we used magnetic graphene oxide (NGO/SPIONs) nanoparticles coated with PLGA polymer as a dynamic nanocarrier for IUdR and, evaluated its sensitizing enhancement ratio in combination with a single dose X-ray at clinically megavoltage energies for treatment of C6 glioma rats. Nanoparticles were characterized using Zetasizer and TEM microscopy, and in vitro biocompatibility of nanoparticles was assessed with MTT assay. IUdR/MNPs were intravenously administered under a magnetic field (1.3 T) on day 13 after the implantation of C6 cells. After a day following the injection, rats exposed with radiation (8 Gy). ICP-OES analysis data indicated an effective magnetic targeting, leading to remarkably improved penetration through the BBB. In vivo release analysis with HPLC indicated sustained release of IUdR and, prolonged the lifespan in plasma (P < .01). In addition, our findings revealed a synergistic effect for IUdR/MNPs coupled with radiation, which significantly inhibited the tumor expansion (>100%), prolonged the survival time (>100%) and suppressed the anti-apoptotic response of glioma rats by increasing Bax/Bcl-2 ratio (2.13-fold) in compared with the radiation-only. In conclusion, besides high accumulation in targeted tumor sites, the newly developed IUdR/MNPs, also exhibited the ability of IUdR/MNPs to significantly enhance radiosensitizing effect, improve therapeutic efficacy and increase toxicity for glioma-bearing rats. 10.1016/j.jphotobiol.2020.111827
    Graphene oxide-PLGA hybrid nanofibres for the local delivery of IGF-1 and BDNF in spinal cord repair. Pan Su,Qi Zhiping,Li Qiuju,Ma Yue,Fu Chuan,Zheng Shuang,Kong Weijian,Liu Qinyi,Yang Xiaoyu Artificial cells, nanomedicine, and biotechnology Spinal cord injury (SCI) can lead to permanent and severe functional impairment below the lesion level and is still one of the most challenging clinical problems. The treatment of SCI has progressed with the development of tissue engineering techniques. Insulin-like growth factor 1 (IGF-1) and brain-derived neurotrophic factor (BDNF) are growth factors closely related to nerve regeneration. In this study, IGF-1 and BDNF were successfully immobilized on biodegradable graphene oxide (GO)-incorporated PLGA (PLGA/GO) electrospun nanofibres. The effect of PLGA/GO nanofibres with immobilized IGF-1 and BDNF on neurogenesis was investigated in vitro and in vivo utilizing MTT assays, immunofluorescence, motor function detection and histology observations. We demonstrated that PLGA/GO nanofibres loaded with IGF-1 and BDNF not only protected NSCs from oxidative stress induced by HO but also enhanced NSC proliferation and neuronal differentiation in vitro. The in vivo study of an SCI animal model demonstrated that local delivery of IGF-1 and BDNF immobilized to PLGA/GO nanofibres significantly improved functional locomotor recovery, reduced cavity formation and increased the number of neurons at the injury site. Our study indicated that PLGA/GO is an effective carrier for IGF-1 and BDNF delivery and that immobilization of IGF-1 and BDNF onto PLGA/GO nanofibres has a great potential as a nerve implant for spinal cord injury applications. 10.1080/21691401.2019.1575843
    Enhancing Cell Proliferation and Osteogenic Differentiation of MC3T3-E1 Pre-osteoblasts by BMP-2 Delivery in Graphene Oxide-Incorporated PLGA/HA Biodegradable Microcarriers. Fu Chuan,Yang Xiaoyu,Tan Shulian,Song Liangsong Scientific reports Lack of bioactivity has seriously restricted the development of biodegradable implants for bone tissue engineering. Therefore, surface modification of the composite is crucial to improve the osteointegration for bone regeneration. Bone morphogenetic protein-2 (BMP-2), a key factor in inducing osteogenesis and promoting bone regeneration, has been widely used in various clinical therapeutic trials. In this study, BMP-2 was successfully immobilized on graphene oxide-incorporated PLGA/HA (GO-PLGA/HA) biodegradable microcarriers. Our study demonstrated that the graphene oxide (GO) facilitated the simple and highly efficient immobilization of peptides on PLGA/HA microcarriers within 120 min. To further test in vitro, MC3T3-E1 cells were cultured on different microcarriers to observe various cellular activities. It was found that GO and HA significantly enhanced cell adhesion and proliferation. More importantly, the immobilization of BMP-2 onto the GO-PLGA/HA microcarriers resulted in significantly greater osteogenic differentiation of cells in vitro, as indicated by the alkaline phosphate activity test, quantitative real-time polymerase chain reaction analysis, immunofluorescence staining and mineralization on the deposited substrates. Findings from this study revealed that the method to use GO-PLGA/HA microcarriers for immobilizing BMP-2 has a great potential for the enhancement of the osseointegration of bone implants. 10.1038/s41598-017-12935-x
    Graphene Oxide Immobilized PLGA-polydopamine Nanofibrous Scaffolds for Growth Inhibition of Colon Cancer Cells. Chen Minmin,Jiang Suwei,Zhang Feng,Li Linlin,Hu Hailiang,Wang Hualin Macromolecular bioscience Graphene oxide (GO)/poly (lactide-co-glycolic acid) (PLGA) scaffolds have promising applications in the biomedical field. However, greater attention is focused on the incorporated system and its applications in normal cells. In this work, a novel GO immobilized PLGA nanofibrous scaffold assisted by polydopamine (PLGA-PDA-GO) is developed for growth inhibition of HT-29 colon cancer cells. The interactions between GO and PDA are attributed to a π-π conjugate interaction and electrostatic attraction. In addition to the enhancement of thermal stability and mechanical strength, the surface roughness, hydrophilicity, and electro-activity of the scaffolds are significantly improved by immobilization of GO. The scaffolds show good inhibition of HT-29, and immobilized GO is observed to be in contact with but not internalized in HT-29 cells. The cytotoxicity mechanism of scaffolds toward HT-29 is attributed to intracellular activated reactive oxygen species that result from the physical interaction of the sharp GO edges and electrical signals of π-π stacking between PDA and GO. 10.1002/mabi.201800321