Abstract: Nano Pt/dimercaptosuccinic amide copper (II) (CuL) modified electrode (Au/CuL/nano Pt CME) was prepared by electrodepositing nano crystalline Pt on the surface of CuL monolayer, which was self-assembled on Au electrode (Au/CuL CME). The electrode’s electrochemical response was studied by cyclic voltammetry (CV) and its surface was characterized by scanning electron micrograph (SEM), atomic force microscope (AFM), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectrum(XPS). The results indicated that the biosensor displayed excellent electrocatalytical response to the reduction of H2O2 in 0.02 mol·L-1 PBS(pH=6.0). The electrode responsed to H2O2 in the concentration range of 0.00125-0.16mmol·L-1with detection limit of 0.3 μmol·L-1 (signal/noise ratio was 3). Meanwhile, the electrode showed good sensitivity (0.312 mA·cm-2·mmol-1·L in amperometric measurements), rapid response time (4.3 s), and reproducibility for long-termuse (the variation coefficients were 3.1%and 3.9% (n=10) at 46 μmol·L-1 and 2.8 mmol·L-1 H2O2, respectively; the current maintained 95%for at least more than 70 days to 10 μmol·L-1 H2O2).

Key words: Nano Pt modified electrode, Dimercaptosuccinic amide copper (II), Electrocatalytic reduction, H2O2, Cyclic voltammetry