Excitation- emission matrix fluorescence spectroscopy combined with three-way chemometrics analysis to follow denatured states of secondary structure of bovine serum albumin

Monitoring the secondary structure of proteins is surely important in different biochemical and biophysical interactions. In this study, estimation of changes in secondary structure motifs of bovine serum albumin were done by means of fluorescence spectroscopy coupled by parallel factor analysis (PARAFAC) method. Different parameters such as core consistency, number of iteration and residual sum of squares were used to estimate optimum number of components in PARAFAC of fluorescence spectra and finally three components were utilized for resolving spectra. After curve resolution based on PARAFAC using suitable constrains such as nonnegativity and unimodality, concentration profiles of the resolved components were compared by the results of the secondary structure analysis based on circular dichroism (CD). An interesting agreement was detected between the concentration profiles of two components with variation of α-helix and random coil during chemical denaturation.