Simultaneous detection of four glucocorticoids by graphene-chitosan\ nanogold\glucocorticoid receptor bioimmunosensor

In this study, a sandwich-type immunoassay was employed for the simultaneous detection of four glucocorticoids (cortisone, clobetasol 17-propionate, triamcinolone, and dexamethasone) using graphene (GNP)-chitosan (CHI)\nanogold\glucocorticoid receptor (GR) bioimmunosensor. A novel strategy was developed, which involved the integration of surface modification technology, electrochemical detection technology, and immunoassay technology. The electrochemical characteristics of the modified bioimmunosensor were investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods. The GR concentration and incubation time were optimized to achieve the best detection effect. The differential pulse voltammetry (DPV) response sequence based on the identical concentration level was found to be cortisone > clobetasol 17-propionate > triamcinolone > dexamethasone. The bioimmunosensor demonstrated excellent performance characteristics with a wider linear range of 0.5–7000 ng⋅mL −1 , lower detection limit of 0.071–0.106 ng⋅mL −1 , better stability and repeatability. Cortisone and clobetasol 17-propionate were detected in skincare samples and achieved satisfactory test results.