Potentialities of differently-stabilized silver nanoparticles for spectrophotometric determination of peroxides

One of the possible ways for using silver nanoparticles (AgNPs) in spectrophotometry is their application for the determination of oxidizing agents, based on oxidative destruction of these nanoobjects. This process depends on the structure of AgNPs surface layer, which is essentially affected by the chosen stabilizer. To assess influence of the nanoparticle stabilizer and the nature of the analyte, possibilities of AgNPs covered with stabilizers of three types (citrate, polyvinylpyrrolidone, and polyhexamethylene guanidinium) for the spectrophotometric determination of hydrogen peroxide and differently substituted organic peroxides were studied. The approach is based on AgNPs oxidation leading to discoloration of the solution monitored spectrophotometrically. Different selectivity of the oxidation depending on the stabilizer was shown. Effects of various factors (time of interaction, pH, concentration of AgNPs) on the oxidation and analytical performance of the procedure were investigated. The method allows for the determination of hydrogen peroxide, peracetic acid, m-chloroperbenzoic acid, and t-butylhydroperoxide in the range of 0.3-1.5, 0.1-0.8, 1.0-7.5, and 1-7 μg mL^-1 and with the limits of detection of 0.1, 0.04, 0.3, and 0.3 μg mL^-1, respectively. The analysis can be performed using either spectrophotometry or naked-eye detection.