A label-free strategy for H2O2 assay by chemical vapor generation-atomic fluorescence spectrometry

Hydrogen peroxide (H2O2) plays an essential role as a signal molecule in regulating diverse biological processes. It is of practical significance for accurately detecting the concentration of H2O2. In this work, a simple and label -free method was developed for H2O2 assay by chemical vapor generation-atomic fluorescence spectrometry (CVG-AFS). The assay was based on the phenomenon that L-Cysteine (L-Cys) can inhibit the AFS signal of As(III), while L-Cys can be oxidized to cystine by H2O2 and I-. Therefore, the concentration of H2O2 was proportion to the AFS signal. Under the optimal experimental conditions, a good linear range from 50 mu M-4 mM was obtained, and the limit of detection (LODs) and relative standard deviation (RSD, n = 7) were calculated to be 9.9 mu M and 0.4%, respectively. The proposed method has been successfully applied for H2O2 assay in medical disinfectants with good recoveries. It has the advantages of simple and cost-effective.

Automated summary

A simple and label-free method was developed for hydrogen peroxide (H2O2) assay by chemical vapor generation-atomic fluorescence spectrometry. The method is based on the inhibition of the atomic fluorescence signal of As(III) by L-Cysteine (L-Cys) and the oxidation of L-Cys to cystine by H2O2 and I-. The proposed method has the advantages of simplicity and cost-effectiveness.