▎ 摘 要
A differential pulse voltammetry (DPV) platform for the sensing of human immunodeficiency virus (HIV) gene was described through the self-assembling of amino-reduced graphene oxide (NH2-rGO) and beta-cyclodextrin (beta-CD) on the surface of glassy carbon electrode (GCE). It is making use of the single-stranded DNA (ssDNA) with sequence hybridized with HIV gene. The ssDNA was attached on NH2-rGO/beta-CD modified GCE (NH2-rGO/beta-CD/GCE) surface, then methylene blue (MB) was interacted with ssDNA to general obvious DPV signal. The HIV gene was then initiated to hybridize with ssDNA on NH2-rGO/beta-CD/GCE surface, causing a dramatic decrease in DPV response of MB at potential of -0.25 V (vs. Ag/AgCl). Under optimal experimental conditions, response was linear in the 0.05 pM to 1 pM HIV gene concentration range. The electrochemical biosensor displayed an ultrahigh sensitivity with detection limit of 8.7 fM and excellent selectivity. The modified electrode displayed good reproducibility, ultra-high sensitivity, and terrific selectivity. This electrochemical biosensor was successfully used for the determination of HIV gene in human serum samples.