aIn this work rank annihilation factor analysis (RAFA) is used to analyze difference spectra of kineticspectrophotometric data. Annihilation of the contribution of one chemical component from the original data matrix is a general method in RAFA. However, sometimes RAFA is not suitable for studying rank deficient data such as kinetic-spectrophotometric measurements. On the other hand, in order to apply RAFA for the determination of an analyte in an unknown sample, a standard two-way matrix of the analyte with rank one should generally be available. This is not usually attainable for kinetic-spectrophotometric monitoring of complexation reactions. Processes monitored by difference spectroscopy always have the spectrum of the initial stage subtracted from each spectrum in the data matrix. In this work we show that, for kinetic-spectrophotometric data of complexation reactions, the spectrum of ligand (reactant) itself can be used as initial spectrum for subtraction. The obtained difference matrix of sample and that of analyte of interest will be full-rank and rank 1, respectively. Therefore the system can be analyzed by RAFA. The proposed method was investigated with simulated data at the first stage. The method was then applied in the analysis of experimental kinetic-spectrophotometric data of a complexation reactions of Co(II) and Ni(II) with chromogenic reagent 1-(2-pyridylazo) 2-naphthol in order to do multi-component determination of these ions in various real samples.

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Um método novo é proposto para resolver dados de cinética-espectrométrica de misturas do tipo multicomponentes e para a determinação de analito(s) na presença de matriz desconhecida. O método utiliza dados de matrizes de variação pelo deslocamento de alvo, denominado espaço de reação. A matriz de variação é obtida pela subtração do espectro do ponto-zero (isto é, primeiro espectro) de cada espectro a cada tempo. Este deslocamento espacial diminui os números de classificação para os números de reações. A resolução da curva de auto-modelagem é usada para resolver as matrizes dos dados de cinética-espectrométrica por matrizes de analitos. Além do mais, o método de adição padrão de segunda ordem é usado para remover o efeito(s) das matrizes para quando se analisa amostras desconhecidas. Isto significa que, a análise quantitativa pode ser realizada pela argumentação da matriz de variação das amostras desconhecidas e amostras adicionadas de padrão e, em seguida, traçar a curva de calibração de adição de padrão. A aplicabilidade do método proposto é avaliada usando dados modelo e real de misturas de analitos.A new method is proposed to resolve the kinetic-spectrophotometric data of multicomponent mixtures and determination of analyte(s) in the presence of unknown matrix. The method uses variation matrix data by shifting to another target, namely the reaction space. The variation matrix is obtained by subtracting the zero-point spectrum (e.g., first spectrum) from each spectrum at each time. This space shifting decreases the rank numbers to the numbers of reactions. Self-modeling curve resolution is used to resolve the variation matrices of kinetic-spectrophotometric data for mixtures of analytes. In addition, second-order standard addition method is used to remove the matrix effect(s) when analyze unknown samples. This means that, quantitative analysis can be performed by augmentation of the variation matrix of the unknown samples and standard added samples and, then, plotting standard addition calibration curve. The applicability of the proposed method is evaluated using model and real data for mixtures of analytes.