Curve resolution procedure for isolating the spectra of unknown interferences from the sample spectrum in analyte determinations

The method described is based on the selection of a wavelength in the sampl e spectrum that is called 'reference wavelength', all measured wavelengths are previously assayed in order to select this reference wavelength. Severa l wavelengths can be used as the reference. The interferent spectrum is cal culated as a function of the interferent absorbance at this wavelength, mak ing use of the ratio between the absorbance of the analyte at the selected wavelength and at every measured wavelength. The proposed methodology can e stimate the unknown interferent spectrum from the sample and pure analyte s pectra. As a quality guarantee of the estimated spectrum, its shape is also estimated in spiked samples. Several samples were analysed, eight being ph armaceutical samples and the others synthetic. Good results were obtained f or all of them.