Simultaneous kinetic spectrophotometric determination of Cu(II), Co(II) and Ni(II) using partial least squares (PLS) regression

Abstract

A partial least squares (PLS-1) calibration model based on kinetic--spectrophotometric measurement, for the simultaneous determination of Cu(II), Ni(II) and Co(II) ions is described. The method was based on the difference in the rate of the reaction between Co(II), Ni(II) and Cu(II) ions with 1-(2-pyridylazo)2-naphthol in a pH 5.8 buffer solution and in micellar media at 25 o C. The absorption kinetic profiles of the solutions were monitored by measuring the absorbance at 570 nm at 2 s intervals during the time range of 0 -10 min after initiation of the reaction. The experimental calibration matrix for the partial least squares (PLS-1) model was designed with 30 samples. The cross-validation method was used for selecting the number of factors. The results showed that simultaneous determination could be performed in the range 0.1-2 µg mL -1 for each cation. The proposed method was successfully applied to the simultaneous determination of Cu(II), Ni(II) and Co(II) ions in water and in synthetic alloy samples.

Simultaneous kinetic spectrophotometric determination of Sn(II) and Co(II) by the calculation of the variation of ratio kinetic profiles

“…Concomi tant determination of metal cations by UV vis spec trophotometry requires a non selective chromogenic reagent [7]. Different chelating agents are known, such as 4 (2 pyridilazo)resorcinol (PAR), 1 (2 pyridylazo) 2 naphthol (PAN), diethyldithiocarbam ate and 1,10 phenanthroline (Phen) [8][9][10][11].…”

Application of H-Point Standard Addition Method and Multivariate Calibration Methods to the Simultaneous Kinetic-Potentiometric Determination of Cerium(IV) and Dichoromate

“…These methods are based on a first calibration step in which a mathematical model is built using a chemical data set (e.g., potential values) and a concentration matrix data set [30][31][32][33][34]. The calibration is followed by a prediction set in which this model is used to estimate unknown concentrations of a mixture from kinetic profile.…”