서강대학교

초록/요약

In this research, we developed an electrochemical biosensor which was composed of hemoglobin (Hb)-DNA conjugate on the nanoporous gold thin film (NPGF) for hydrogen peroxide (H2O2) detection. For the first time, Hb and DNA was conjugated as a sensing platform for uniform orientation of Hb on the electrode. The newly developed Hb-DNA conjugate was designed to prevent Hb from aggregation on the electrode. DNA hybridization of Hb-DNA conjugate and complementary DNA (cDNA) on the NPGF electrode induced uniformly assembled biosensor. Furthermore, the NPGF electrode fabrication method was introduced to the increment of the surface area. To confirm the conjugation of Hb-DNA conjugate, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and ultraviolet-visible spectroscopy (UV-VIS) were used. Formation of the NPGF electrode was verified by scanning electron microscope (SEM). Atomic force microscopy (AFM) was operated for the confirmation of Hb-DNA immobilization on electrode. The electrochemical property of fabricated electrode was investigated by cyclic voltammetry (CV). Also, H2O2 sensing performance of fabricated electrode was investigated by amperometric i-t curve technique. This sensor showed a wide linear range from 0.00025 to 5.00 mM and a correlation coefficient of R = 0.9986. The detection limit was 250 nM. This proposed biosensor can be utilized as a sensing platform for development of biosensor.