Sensitive Aptasensing of Hepatitis B Viral Antigen Gold Dielectrode by Current-Volt Measurements

Abstract

Hepatitis B virus (HBV) is a serious human health issue, primarily leading to cirrhosis, chronic hepatitis, and primary liver cancer. Patients are at higher risk of a poor prognosis if the viral load exceeds >105 copies/mL; hence, it is crucial to identify the early stages of HBV infection. This research aimed to identify hepatitis B surface antigen (HBsAg) on an interdigitated gold electrode sensor assisted by HBsAg-specific aptamer and antibody interactions. The aptamer-HBsAg-antibody sandwich assay was carried out on an interdigitated electrode using aptamer as the capture molecule and anti-HBsAg antibody as the detection molecule. Higher capture probe immobilization was achieved through the gold nanourchin conjugated capture aptamer. On the aptamer-attached electrode, HBsAg interacted with and was sandwiched by the detection antibody. The sandwich assay lowered the limit of HBsAg detection to 0.1 ng/mL, as indicated by the calculated R2 value of 0.9915 on a linear regression graph presenting data for concentrations of HBsAg from 0.1 to 60 ng/mL. Furthermore, specific HBsAg detection was confirmed by complementarity of the capture aptamer sequence and nonspecific proteins (hepatitis C-the core antigen (HCVcoreAg) and albumin). A selective experiment revealed a gradual increase in current responses in a HBsAg-spiked serum sample, demonstrating the interference-free detection of HBsAg for the real-life sample.