ZnSe nanodisks:Ti3C2 MXenes-modified electrode for nucleic acid liquid biopsy with photoelectrochemical strategy

ZnSe nanodisks:Ti3C2 MXene complex was prepared for the first time. Based on its remarkable photoelectrochemical performance, combined with the enzyme-free toehold-mediated strand displacement reaction, a photoelectrochemical biosensor for the detection of the non-small-cell cancer biomarker ctDNA KRAS G12D was developed. ZnSe nanodisks were in situ grown on Ti3C2 MXene surface by two-step hydrothermal method. The high conductivity and adjustable band gap of MXene significantly enhanced the photoelectric response of ZnSe. Subsequently, the photoelectrochemical biosensor was prepared by combining with the signal amplification function of p-aminophenol and the enzyme-free toehold-mediated strand displacement reaction on the modified ITO electrode surface. Under the optimized conditions, the linear detection range is 0.5 similar to 100.0 fM, and the detection limit is 0.2 fM, which realizes the sensitive detection of KRAS G12D. The photoelectrochemical biosensor constructed opens up a new pathway for the preparation of new Mxene-based composite materials and the research of photoelectrochemical biosensor.

Automated summary

ZnSe nanodisks:Ti3C2 MXene complex was prepared and applied to develop a photoelectrochemical biosensor for the sensitive detection of an non-small-cell cancer biomarker ctDNA KRAS G12D. The composite showed remarkable photoelectrochemical performance and, when combined with signal amplification, enabled accurate detection of KRAS G12D.