In recent years, graphene biosensors have received much attention due to their high sensitivity, low noise and low detection limit. Vertical graphene field effect transistors (VGFETs) based on graphene/semiconductor heterojunctions are characterized by high switching ratios and have wide application prospects. In this study, we prepared the ion-gel gate VGFETs and used them for bovine serum albumin (BSA) quantification sensors. The results showed that the adsorption of BSA molecules on the substrate surface was maximized when the ionic strength was 10−3M. The limit of detection (LOD) of BSA concentration was 1μg/ml, suitable for simple and rapid quantitative analysis of protein molecules.
