6533b837fe1ef96bd12a3445

RESEARCH PRODUCT

Simultaneous spectrophotometric determination of calcium and magnesium in mineral waters by means of multivariate partial least-squares regression.

M.j. Medina-hernándezF. BlascoSalvador SagradoFacundo M. Fernández

subject

AnalyteMultivariate statisticsAnalytical chemistrychemistry.chemical_elementCalciumBiochemistrySensitivity and SpecificityAnalytical Chemistrychemistry.chemical_compoundSpectrophotometryPartial least squares regressionElectrochemistrymedicineEnvironmental ChemistryMagnesiumLeast-Squares AnalysisSpectroscopyMineralmedicine.diagnostic_testMagnesiumchemistrySpectrophotometryMultivariate AnalysisCalciumMineral WatersTriarylmethane dye

description

A method for simultaneous spectrophotometric determination of calcium and magnesium in mineral waters using multivariate calibration methods is proposed. The method is based on the development of the reaction between the analytes and Methylthymol Blue at pH 11. Two operational modes were used: static (spectral information) and flow injection (FI) (spectral and kinetic information). The selection of variables was studied. A series of synthetic solutions containing different concentrations of calcium and magnesium were used to check the prediction ability of the partial least-squares models. The method was applied to the analysis of mineral waters and the results were compared with those obtained by complexometry. No significant differences at the 95% confidence level were found. The proposed method is simple, accurate and reproducible, and it could be easily adapted as a portable (static mode) or automatic (FI) method.

10.1039/a608244khttps://pubmed.ncbi.nlm.nih.gov/9330035