Sensitive Near-Infrared Fluorescent Determination of Hydrogen Peroxide and Glucose Using Glutathione-Coated Gold Nanoparticles

Abstract

Near-infrared luminescence glutathione-coated gold nanoparticles (NGS-AuNPs) were synthesized and employed as fluorescent probes for the selective determination of hydrogen peroxide and glucose. This approach was based upon the coordination-induced fluorescence quenching of tris(2-carboxyethyl)phosphine (TCEP) with the NGS-AuNPs and its reduction of H2O2. The NGS-AuNPs possessed a highly monodispersed spherical morphology with a uniform diameter of 2.1 ± 0.5 nm and a maximal fluorescence emission wavelength of 810 nm. The results of the H2O2 determination demonstrate the excellent selectivity of this strategy with a limit of detection of 5.4 μM. This system was also employed for the selective determination of glucose which generated H2O2 by the catalytic oxidation of glucose oxidase with a limit of detection of 0.42 μM. This strategy exhibited excellent performance for the test of H2O2 and glucose in urine with recoveries from 93% to 103%. This methodology may allow the analysis of biological samples and clinical diagnosis.