A voltammetric epithelial sodium channels immunosensor using screen printed carbon electrode modified with reduced graphene oxide

Epithelial sodium channels (ENaC) is a protein that plays a role in maintaining sodium levels and can be used as a biomarker of hypertension. This study aims to develop an electrochemical immunosensor for detecting ENaC using a screen-printed carbon electrode (SPCE), which was modified with reduced graphene oxide (RGO). The RGO improves the performance of immunosensor because it contains -COOH groups that can form a covalent bond with the terminal -NH2 of anti-ENaC. The result shows that the optimum concentration of anti-ENaC was 1.0 g/mL for 30 min incubation time. The various concentration of ENaC has a linear relationship with the decreasing of ferricyanide peak current signal with the range of 0.01-1.5 ng/mL, and the limit of detection was 0.198 ng/mL. The level of ENaC concentration in urine samples can be used for the realization of a point-of-care device for early detection of hypertension.