MX/MWCNTs composite material aids new strategy for HBV-DNA electrochemical biosensor: achieving multi-level signal amplification and unlabeled detection

作者：Shan Huang, Huihao Li, Mingli Yang, Xinqi Liu, Yi Fang, Qi Xiao, Yue Zhang · 发表于：Advanced Composites and Hybrid Materials · 年份：2025 · DOI：10.1007/s42114-025-01215-2 · 被引用次数：11 · 研究领域：MXene and MAX Phase Materials、Advanced biosensing and bioanalysis techniques、RNA Interference and Gene Delivery

Hepatitis B virus DNA (HBV-DNA) serves as a crucial biomarker for the detection of the hepatitis B virus, with variations in its concentration in blood samples providing vital insights into patient infection and recovery status. We have developed an electrochemical biosensor tailored for HBV-DNA detection, exhibiting high sensitivity, specificity, and a broad detection range. The biosensor utilizes a composite material composed of MXene and multiwalled carbon nanotubes (MX/MWCNTs), prepared through a hand-shaking self-assembly technique, to modify the glassy carbon electrode (GCE) and serve as signal receivers. A meticulously designed padlock probe DNA specifically recognizes HBV-DNA and forms a double-stranded DNA structure, which is subsequently degraded by exonuclease III. The resulting sequence then hybridizes with a PolyT-primer to create template, triggering rolling circle amplification and releasing a substantial amount of pyrophosphate for the initial level of signal amplification. Subsequently, the pyrophosphate induces the release of methylene blue (MB) from MB@ZIF-90 composite, achieving a second level of signal amplification. The released MB is then adsorbed by the MX/MWNCNTs-modified GCE, which possesses cationic dye adsorption capabilities and a large specific surface area, generating a detection signal and completing the third level of amplification. This biosensor offers a detection range spanning from 1.0 pM to 1.0 × 106 pM, with a remarkable detection limit ...