ABILITIES OF DIFFERENTIATION AND PARTIAL LEAST-SQUARES METHODS IN THE ANALYSIS BY DIFFERENTIAL-PULSE POLAROGRAPHY - SIMULTANEOUS DETERMINATION OF FURAZOLIDONE AND FURALTADONE

A comparison between the applicability of two multicomponent analysis methods, differentiation of signals and partial least squares (PLS) methods, to the resolution of overlapping differential pulse polarographic (DPP) peaks corresponding to the irreversible reduction process of two nitrofuran derivatives has been performed. The results show that the derivative DPP signals are not suitable for the resolution of mixtures of these system, by application of the zero-crossing method, because the zero-crossing potential is not independent of the concentration. However, PLS has the capacity of modelling the total evolution of the DPP peaks with the concentration. The PLS multivariate calibration method has been successfully applied to the simultaneous analysis of both compounds in a pharmaceutical formulation.