Application of RBF Artificial Neural Networks to Simultaneous Spectrophotometric Determination of Cadmium,Silver,Copper and Mercury

A new water soluble triazene chromogenic reagent,1-(2,6-dibromo-4-nitro-1-phenyl)-3-(4′-p-sulfinoethylol-sulfo-phenylazophenyl)-triazene,was synthesized,and its optimum conditions of colour reaction with Cd2+,Ag+,Cu2+ and Hg2+ were studied.It was found that relatively large amounts of those commonly co-existing ions were tolerable in the color reactions,but serious interferences were found among the 4 metal ions determined due to the overlapping of absorption spectra of their colored complexes.By applying the chemometrical method of radial basis function (RBF) artificial neural networks (ANN),the above mentioned problem of absorption spectra overlapping was solved and the 4 metal ions were determined simultaneously without separation or using masking agents.Values of absorbance measured at 21 characteristic wavelengths in the range of 460-560 nm were taken as characteristic parameters,and concentrations of the 4 metal ions were found from the output values of RBFANN.The absolute relative errors of the results were less than 6%.