Constructing a label-free electrochemical biosensor based on magnetic α-Fe2O3/Fe3O4 heterogeneous nanosheets for the sensitive detection of VKORC1*2 gene

Abstract

Pharmacogenetic testing technology can effectively determine the individual differences among patients and scientifically assist doctors to select the most suitable drugs for each patient. In this study, an electrochemical biosensor based on magnetic α-Fe2O3/Fe3O4 heterogeneous nanosheets was constructed to detect Vitamin K epoxide reductase complex 1 type AA (VKORC1*2). Firstly, we fabricated magnetic α-Fe2O3/Fe3O4 heterogeneous nanosheets as the substrate material for electrochemical biosensors. Subsequently, the material surface was modified with Au nanoparticles to facilitate the connection of sensing probes and enhance current signal amplification. The electrochemical biosensor showed a negative linear relationship with the concentrations of target DNA (tDNA, VKORC1*2 gene) within 1 pM − 1 μM, a limit of detection was (LOD) = 0.36 pM, and a limit of quantification was (LOQ) = 1.19 pM. The biosensor demonstrated exceptional specificity, reproducibility, and stability. In real sample analysis, it exhibited a recovery range of 96.63 % − 110.57 % (RSD ≤ 3.07 %) for various tDNA concentrations, thereby indicating its promising potential in clinical diagnostics.

Keywords

• Electrochemical biosensor
• Magnetic α-Fe2O3/Fe3O4 heterogeneous nanosheets
• Magnetic self-assembly
• ssDNA probes
• VKORC1*2