Analysis of metal ion concentration in humic acid by excitation-emission matrix fluorescence and chemometric methods

In this study, using a representative system of a humic acid sample (Aldrich), a method for the quantification of the interaction of metal ions (Cu(II), Pb(II), Cd(II), Zn(II)) with HA has been developed by combining EEMF and chemometrics. N-way partial least squares regression (N-PLS) and parallel factor analysis (PARAFAC) have been effectively applied to the fluorescence data of HA samples having varying metal ion concentrations. The accuracy of the method, as evaluated from the root mean square error of prediction (RMSEP) value, is found to be very good in the case of Cu and Pb. © 2009 Springer Science+Business Media, Inc.