Window factor analysis of methylene blue in water
The aggregation of methylene blue (MB) in water was studied by factor analysis (FA) of the visible spectra over a wide range of concentration from 1.000 x 10(-7) to 1.600 x 10(-2) M. Abstract factor analysis of data with multiple sources of error (AFA-MSE) revealed three MB species. The concentration profiles and spectra of the species were extracted by window factor analysis (WFA). The profiles were interpreted to be due to MB monomer, dimer and a trimer containing one chlorine atom. The dissociation constants of the dimer and trimer were determined to be 1.5 x 10(-4) M and 3.2 x 10(-11) M-3 respectively. Copyright (C) 1999 John Wiley & Sons, Ltd.
window factor analysis factor analysis methylene blue chemometrics visible spectroscopy