Workplace monitoring of gas phase hydrogen peroxide by means of fluorescence spectroscopy Original Research Article

A novel method for workplace monitoring of gas phase hydrogen peroxide is described. It is based on the dimerization of p-hydroxyphenylacetic acid (p-HPA) by hydrogen peroxide in the presence of peroxidase as catalyst. The fluorescent dimer of p-HPA is quantified by means of fluorescence spectroscopy. The use of a microplate fluorophotometer allows for high sample throughput. Gas phase sampling was carried out with impingers containing different types of sampling media. The new method meets easily with the required sensitivity for gas phase monitoring of H2O2 in an industrial environment. For a 10 l air sample, the linear range of calibration covers the concentrations from 0.04 to 6 times the maximum allowable concentration (MAK) value of 1 ppmv (1.4 mg/m3), thus allowing for workplace monitoring of the analyte. This method is validated with a photometric method using 2,2′-azino-bis(3-ethylbenzothiazoline)-6-sulfonate diammonium salt) (ABTS) as reagent.