Novel hybridization indicator for DNA sequences related to the hepatitis B virus: Electrochemical and in-silico approach

Abstract

In the present study, esculetin, as a novel electroactive indicator, was used to produce an electrochemical DNA hybridization biosensor for Hepatitis B Virus (HBV) detection. At first, alkanothiol-modified DNA probe (from Hepatitis B) was self-assembled on the surface of a glassy carbon electrode modified by the nanocomposite of polyaniline and Au nanoparticles (PANI-Au). Hybridization conditions were enhanced, including the immobilization of the probe strands, the hybridization process and the indicator accumulation. For evaluating the DNA hybridization, the differential pulse voltammetric response of the accumulated esculetin was used as an electroactive indicator on different electrode surfaces. According to the obtained results, the voltammetric responses of esculetin accumulated on the probes interacted with non-complementary, mismatch and complementary targets were significantly different. Therefore, in optimum conditions, electrochemical signals of esculetin were linear in the concentration range of 0.01–3.00 × 10−6 M of the complementary strands, and a detection limit of 3.80 × 10−9 M was obtained for the target. Subsequently, the modified electrode was utilized for the detection of the HBV in spiked serum and plasma samples. The results obtained from electrochemical technique were confirmed by computational molecular simulation using MOE software. Moreover, the simulation outcomes provided valuable information about quantum chemical properties including the HOMO–LUMO maps and chemical reactivity for esculetin-the DNA target components.