High sensitivity and rapid detection of hepatitis B virus DNA using lateral flow biosensors based on Au@Pt nanorods in the absence of hydrogen peroxide

Abstract

Nanozymes are a kind of nanomaterial with enzymatic activity, and have attracted wide attention in signal probe fields owing to their good catalytic activity and stability. Herein, we designed gold@platinum nanorods (Au@Pt) with enhanced oxidase-like activity as signal probes to construct lateral flow biosensors (LFBs) for the detection of hepatitis B virus DNA (HBV-DNA). The enhanced oxidase-like activity of Au@Pt nanorods can effectively catalyze the oxidation of 3,3′,5,5′-tetramethylenebenzidine (TMB) to a blue substrate in the absence of hydrogen peroxide (H₂O₂). Based on this principle, LFBs using Au@Pt nanorods as signal probes can provide an effective signal amplification strategy and prevent biomolecules from being affected by H₂O₂. Under optimal conditions, LFBs have a good linear relationship between 0.1 nM and 50 nM, and the calculated detection limit was 8.5 pM. The technological strategy in the detection and quantification of HBV-DNA in this work may be helpful to achieve a rapid and accurate diagnosis of early HBV-DNA and provide new ideas for the development of point-of-care testing.