A simple procedure for the quantitative determination of mixtures of nitrophenols pollutants in environmental and biological samples based on continuous spectrophotometric acid–base titrations and multivariate curve resolution has been proposed. The procedure simultaneously takes into account the spectroscopic and acid– base properties of the nitrophenols, which leads to a higher selectivity. The quantitative determination of analyte in the presence of unknown and uncalibrated interferences is a general benefit of the method. Moreover, only one single synthetic standard containing of the analyte of interest is enough to perform the analysis. Because of the rank-deficiency phenomena, the pure spectra and concentration profiles of the species of interest can only be recovered through matrix augmentation. Even in the presence of the rank deficiencies, in most cases accurate quantitation with relative errors in prediction lower than 5 % was obtained. The percent recoveries obtained (92–108 %) were satisfactory.
