Study of the interaction between collagen and naturalized commercial dyes by Fourier infrared spectroscopy and thermogravimetric analysis

Naturalized dyes and traditional dyes are compared through the study of leather dyeing process. The interactions between each class of dyes and the leather proteins were studied by FT.IR spectroscopy and thermigravimetric analyses. The protein cross-linking of the dyed leathe was evaluated by studying the 1654/1690 CM-1 peak height ratio and a deconvolution procedure of the amide I peak. The elix secondary structure was the predominant component of the leather proteins of the samples dyed with low concentrated nat. dyes, while beta-sheets prevailed when leather sample dyed with traditional materials at high concentrat. The data were compared with thermogravimetric results, and a final discussion takes place