Determination of hydrogen sulfide and hydrogen peroxide in complex samples of milk and urine by spectroscopic standard addition data and chemometrics methods

Abstract

Spectroscopic data of standard additions were collected and used to calculate the spectrum of the unknown interferent(s) based on the net analyte signal. The proposed method was named net analyte signal interferent modelling (NAS-IM). In the next step, an H-point standard addition method was used to obtain the concentration of the analyte in the sample. The method was applied to determine hydrogen sulfide and hydrogen peroxide in urine and milk samples, respectively. The results of the method were validated by analysis of the second-order data of the same samples by multivariate curve resolution-alternating least squares (MCR-ALS) and parallel factor analysis (PARAFAC). The concentration of the analytes calculated by NAS-IM and second-order methods has a maximum difference of 7.7%.