CRISPR-Cas12a-regulated DNA adsorption and metallization on MXenes as enhanced enzyme mimics for sensitive colorimetric detection of hepatitis B virus DNA.
Tao Yu,Yi Ke,Wang Haixia,Kim Hae-Won,Li Kai,Zhu Xiang,Li Mingqiang
Journal of colloid and interface science
Hepatitis B virus (HBV) infection is closely associated with the high risk of evolving into human hepatitis diseases including chronic hepatitis, liver fibrosis and cirrhosis, as well as hepatoma. Although various methods have been developed for HBV DNA detection, most of them either rely on expensive instruments or laborious procedures involving professional personnel. In this study, we for the first time established the CRISPR-Cas12a based colorimetric biosensor for target HBV detection by utilizing probe DNA regulation of the catalytic behaviors of Mxene-probe DNA-Ag/Pt nanohybrids. In the presence of HBV target, the Cas12a trans-cleavage activity could be efficiently activated to degrade the DNA probes, which led to the inhibition of DNA metallization and enzyme activity enhancer DNA adsorbed on Mxene, resulting in significantly reduced catalytic activity. The Mxene-probe DNA-Ag/Pt nanohybrids exhibited excellent sensitivity and specificity with subpicomolar detection limits, as well as good accuracy and stability for the determination of target HBV DNA in human serum samples. Moreover, this colorimetric sensing strategy could be integrated with the smartphone platform to allow the visible sensitive detection of target DNA. Taken together, the proposed colorimetric method provides a novel approach for HBV DNA diagnosis, especially suitable for the high endemic, developing countries with limited instrumental and medical supports.
10.1016/j.jcis.2022.01.038
Fast-response electrochemical biosensor based on a truncated aptamer and MXene heterolayer for West Nile virus detection in human serum.
Bioelectrochemistry (Amsterdam, Netherlands)
West Nile virus (WNV) is a mosquito-borne flavivirus that can cause West Nile fever, meningitis, encephalitis, and polio. Early detection of WNV is important to prevent infection spread on the field. To commercialize the electrochemical biosensor for WNV, rapid target detection with the cheap manufacture cost is essential. Here, we developed a fast-response electrochemical biosensor consisting of a truncated WNV aptamer/MXene (TiCT) bilayer on round-type micro gap. To reduce the target binding time, the application of the alternating current electrothermal flow (ACEF) technology reduced the target detection time to within 10 min, providing a rapid biosensor platform. The MXene nanosheet improved electrochemical signal amplification, and the aptamer produced through systematic evolution of ligands by exponential enrichment process eliminated unnecessary base sequences via truncation and lowered the manufacturing cost. Under optimized conditions, the WNV limit of detection (LOD) and selectivity were measured using electrochemical measurement methods, including cyclic voltammetry and square wave voltammetry. The LOD was 2.57 pM for WNV diluted in deionized water and 1.06 pM for WNV diluted in 10% human serum. The fabricated electrochemical biosensor has high selectivity and allows rapid detection, suggesting the possibility of future application in the diagnosis of flaviviridae virus.
10.1016/j.bioelechem.2023.108540
A novel electrochemical sandwich-like immunosensor based on carboxyl TiCT MXene and rhodamine b/gold/reduced graphene oxide for .
Niu Huimin,Cai Shumei,Liu Xueke,Huang Xiaoming,Chen Juan,Wang Shuiliang,Zhang Shenghang
Analytical methods : advancing methods and applications
(LM) is one of the most common food-borne pathogens and can induce a series of diseases with a high mortality rate to humans; hence, it is very necessary to develop a highly sensitive method for LM detection. Based on this need, a new sandwich-like electrochemical immunosensing platform was developed herein by preparing carboxyl TiCT MXene (C-TiCT MXene) as the sensing platform and rhodamine b/gold/reduced graphene oxide (RhB/Au/RGO) as the signal amplifier. The high conductivity and large surface area of C-TiCT MXene make it a desirable nanomaterial to fix the primary antibody of LM (PAb), while the prepared Au/RGO/RhB nanohybrid is dedicated to assembling the secondary antibody (SAb) of LM, offering an amplified response signal. Through the use of RhB molecule as the signal probe, the experiments showed that the peak currents of RhB increase along with an increase in the concentration of LM from 10 to 10 CFU mL, and an extremely low limit of detection (2 CFU mL) was obtained on the basis of the proposed immunosensing platform after optimizing various conditions. Hence, it is confirmed that the developed sandwich-like immunosensor based on C-TiCT MXene and RhB/Au/Gr has great application in the detection of LM and other analytes.
10.1039/d1ay02029c
An enhanced SPR optical fiber biosensor using TiCT MXene/AuNPs for label-free and sensitive detection of human IgG.
Nanoscale
Abnormal human immunoglobulin G (IgG) may induce the risk of immune system disorder, infectious diseases, tumors and so on. However, the current detection methods exhibit low sensitivity, which limits their practical application. In this work, an SPR optical fiber sensor (SPR-OFS) with high sensitivity is designed for label-free detection of human IgG. It is fabricated using a heterostructure optical fiber coated with Au film/AuNPs and the TiCT MXene biofunctionalized with goat anti-human IgG by polydopamine (PDA). In the experiment, the optimal thickness of the TiCT MXene was explored and determined to be about 93 nm by comprehensively considering the refractive index (RI) sensitivity and spectral bandwidth of the SPR sensor. When the largest figure of merit (FOM) is calculated to be 17.8279 RIU, its RI sensitivity was ultimately found to be 2804.5 nm per RIU. The SPR-OFS was employed to detect human IgG within the concentration range of 0-30 μg mL and its sensitivity is demonstrated to be 1.7046 nm (μg mL). The SPR-OFS was also proved to have excellent linearity, specificity and stability. The proposed sensor offers outstanding performance with simple fabrication, providing a cutting-edge bioanalytical platform with potential applications in clinical diagnosis.
10.1039/d4nr01883d
Low Dose of Ti C MXene Quantum Dots Mitigate SARS-CoV-2 Infection.
Small methods
MXene QDs (MQDs) have been effectively used in several fields of biomedical research. Considering the role of hyperactivation of immune system in infectious diseases, especially in COVID-19, MQDs stand as a potential candidate as a nanotherapeutic against viral infections. However, the efficacy of MQDs against SARS-CoV-2 infection has not been tested yet. In this study, Ti C MQDs are synthesized and their potential in mitigating SARS-CoV-2 infection is investigated. Physicochemical characterization suggests that MQDs are enriched with abundance of bioactive functional groups such as oxygen, hydrogen, fluorine, and chlorine groups as well as surface titanium oxides. The efficacy of MQDs is tested in VeroE6 cells infected with SARS-CoV-2. These data demonstrate that the treatment with MQDs is able to mitigate multiplication of virus particles, only at very low doses such as 0,15 µg mL . Furthermore, to understand the mechanisms of MQD-mediated anti-COVID properties, global proteomics analysis are performed and determined differentially expressed proteins between MQD-treated and untreated cells. Data reveal that MQDs interfere with the viral life cycle through different mechanisms including the Ca signaling pathway, IFN-α response, virus internalization, replication, and translation. These findings suggest that MQDs can be employed to develop future immunoengineering-based nanotherapeutics strategies against SARS-CoV-2 and other viral infections.
10.1002/smtd.202300044
A TiC-MXene-functionalized LRSPR biosensor based on sandwich amplification for human IgG detection.
Zhao Xueqi,Zhang Yue,Wang Xinghua,Ma Pinyi,Song Daqian,Sun Ying
Analytical and bioanalytical chemistry
Long-range surface plasmon resonance (LRSPR) has demonstrated excellent performance in sensing and detection, due to its higher accuracy and sensitivity compared with conventional surface plasmon resonance (cSPR). In this work, we establish an LRSPR biosensor which employs PDA/TiC-MXene/PDA-gold film as a sensing substrate and gold nanoparticles (AuNPs) as enhancers. TiC-MXene is an emerging two-dimensional (2D) layered material which is used extensively in immunoassay and biosensing. The sensing substrate comprises two polydopamine (PDA) films between which is sandwiched a TiC-MXene film based on a gold film, which provides a large surface area and abundant binding sites to rabbit anti-human IgG (Ab). Sandwich amplification is adopted to enhance the sensitivity of the LRSPR biosensor, and AuNPs/staphylococcal protein A (SPA)/mouse anti-human IgG (Ab) composites are introduced into the flow cell as enhancers after the immune binding of human IgG to Ab. The antigen (human IgG) detection range is 0.075 μg mL to 40 μg mL, and the limit of detection is almost 20 times lower than that for cSPR biosensors. This novel LRSPR biosensor demonstrates excellent performance in immune sensing over a broad detection range and a low limit of detection. Subsequent modification of the LRSPR sensing platform could be made for extensive application in various biological detection fields.
10.1007/s00216-021-03858-8