Highly Sensitive Hepatitis B Virus Identification by Antibody-Aptamer Sandwich Enzyme-Linked Immunosorbent Assay

Hepatitis B virus (HBV) infection is considered a major global health problem, causing various health issues, including cirrhosis, hepatitis, and liver cancer. The risk of developing such complications increases when the viral load is above 105 copies/mL. Early identification of HBV infection is imperative to preventing the spread of infection to other parts of the body. Although various sensing methods have been developed to identify HBV, researchers are still working toward developing cheap, easy, and sensitive detection methods. We developed a highly sensitive and rapid HBV detection method using nanomaterials on enzyme-linked immunosorbent assay (ELISA). Aptamer-antibody was utilized as the detection probe and immobilized on a zeolite-modified ELISA plate to detect the HBV biomarker hepatitis B surface antigen (HBsAg). To enhance the detection of HBsAg, aptamer and antibody were attached to gold nanoparticle through electrostatic interaction and immobilized on the zeolite-modified ELISA plate through amine linker. This probe-modified ELISA plate detected low levels of HBsAg, with a detection limit of 0.1 ng/mL. Furthermore, serum spiked experiments showed increment of absorbance with increasing HBsAg concentration, but control trials with other biomolecules showed no increment of absorbance, showing the specific and selective detection of HBsAg. This nanomaterial-modified ELISA plate can detect low levels of HBsAg and help in the diagnosis of HBV infection in its early stages.