Real-time detection of hepatitis B surface antigen using a hybrid graphene-gold nanoparticle biosensor
Ffion Walters, S. Rozhko, David J. Buckley, E. Ahmadi, Muhammad Munem Ali, Zari Tehrani, Jacob J. Mitchell, Gregory Burwell, Yi Liu, Olga Kazakova, Owen James Guy
Abstract
Abstract A hybrid biosensor based on a graphene resistor functionalized with self-assembled Graphene-AuNPs (Gold Nanoparticles) is demonstrated for the real-time detection of hepatitis B surface antigen (HBsAg). The hybrid biosensor consists of a ssDNA sequence attached to a graphene resistor device via π – π stacking interactions in combination with a ssDNA functionalized AuNP. The ssDNA has complementary sequences which through hybridization, yield the graphene-AuNP hybrid biosensor. Real-time 2-point resistance measurements, performed using varying concentrations of HBsAg, show a linear dependence of resistance change against the logarithm of HBsAg concentration (log[HBsAg]). A limit of detection of 50 pg ml −1 was observed. Moreover, the hybrid biosensor platform has potential to be applied to any biomarker of interest.