Application Of Gold Nanoparticles Modified Electrode In Bioelectroanalysis

The chemically modified electrodes have been duratived reported since they were developed in the middle of 1970'S. It has been widely applied in many areas such as life science, environmental science, analytical science and material science, etc. When some mediators were modified on the electrode, it could be used to facilitate the electron transfer and catalyse the electrochemical reaction. Small size of nano-materials produced many specific phenomena. Gold nanoparticles has been widespread concerned in recent years because of its excellent biological total capacitance and superior catalytic performance. The main works in this thesis include:(1) Gold nanoparticles (GNP) were self-assembled to a L-cysteine modified glassy carbon electrode, which was as a new voltammetric sensor for selective determination of serotonin in human blood serum. This sensor shows a linear voltammetric response for serotonin in the concentration range of 6.0×10-8 to 6×10-6 mol L-1 with detect limit of 2×10-8 mol L-1. The established method possesses excellent selectivity for determination of serotonin in spite of the presence of dopamine, epinephrine, ascorbic acid and folic acid. The veracity was estimated by detecting recovery in healthy human blood serum with average value of 104.67%.(2) The electrochemical behavior of guanine on the gold namoparticles modified electrode was investigated by cyclic voltammetry (CV). It showed that the gold nanoparticles modified electrode possesses an efficient electrocatalytic activity for the electrochemical oxidation of guanine. Differential pulse voltammetric(DPV) was used in this text. The linear range for individual measurement of guanine was 9×10-8-2.9×10-5mol/L with detection limit 7×10-8mol/L. The veracity was estimated by detecting recovery in healthy human blood serum with average value of 104.92%.(3) The electrochemical behavior of adenine on the gold namoparticles modified electrode was investigated by cyclic voltammetry (CV) and the related electrode kinetic parameters were calculated. It showed that the gold nanoparticles modified electrode possesses an efficient electrocatalytic activity for the electrochemical oxidation of guanine. Differential pulse voltammetric(DPV) was used in this text. The linear range for individual measurement of guanine was 9×10-8-3×10-6 mol/L with detection limit 7×10-8mol/L. Adenine can be well selected from guanine and other cations. The veracity was estimated by detecting recovery in healthy human blood serum with average value of 101.28%.