A reliable electrochemical sensor for determination of H2O2 in biological samples using platinum nanoparticles supported graphite/gelatin hydrogel

A sensitive and selective amperometric detection of hydrogen peroxide (H2O2) sensor in biological samples was developed using platinum nanoparticles decorated graphite/gelatin hydrogel (PtNPs@GR/GLN) composite. The GLN hydrogel taking an advantage of dispersing medium as well as supporting agent for selectively welcomes H2O2 molecule on the electrode surface. The PtNPs@GR/GLN composite was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and elemental analysis. The number of PtNPs deposition cycles, effect of scan rate and solution pH were studied and discussed in details. The electrochemical behavior of PtNPs@GR/GLN modified electrode was investigated by cyclic voltammetry (CV) and showed an excellent electrocatalytic activity and lower detection potential towards the sensing of H2O2. Besides, the amperometric i-t curves displayed a fast diffusion and wide linear response range of H2O2 concentrations from 0.05 to 870.6 mu M with a detection limit (LOD) of 37 nM. The PtNPs@GR/GLN modified electrode exhibited selectively detect H2O2 molecule in presence of biologically active interfering molecules. The PtNPs@GR/GLN modified electrode was successfully applied for the determination of H2O2 in biological real samples such as human serum and saliva for practical applications.