Synchrotron X-ray absorption spectroscopy and fluorescence spectroscopy studies of collagen type I-talc intercalated nanocomposites

We investigated the properties of collagen type I-talc intercalated nanocomposites using different tech- niques. Understanding the conformational changes of collagen induced by clay is noticeably lacking, which is pivotal for understanding the structure of collagen-clay hybrid nanocomposites. We aim to investigate the influence of talc clay minerals on the microstructure of collagen type I molecules. Our main goal is to understand the interaction between talc and collagen molecules and to elucidate the microstructure–property relation of intercalated hybrid nanocomposites. The FT-IR spectrum of collagen type I-talc confirmed the presence of collagen amide bands and talc silicate bonds. Also, the differen- tial scanning calorimetry (DSC) result showed that the addition of talc to the matrix could increase the denaturation temperature (T d = 40.8 °C) compared to pure collagen (T d = 19 °C). The fluorescence inten- sity increased in collagen type I-talc nanocomposites, indicating that the interaction of talc with collagen chains in collagen type I-talc dispersion varies the micro-environment of the tyrosine amino acids in the collagen fibrils and its fluorescence. We also analyzed X-ray absorption spectroscopy (XAS) in to- tal fluorescence yield (TFY) and total energy yield (TEY) modes of pure collagen and collagen type I-talc nanocomposites prepared at different concentrations of talc and at different temperatures (4 °C, 8 °C, and 14 °C). We have found that the synthesis conditions have a considerable effect on the local atomic envi- ronments of nitrogen, carbon, and oxygen atoms in collagen type I-talc nanocomposites. These results are of significance for developing new applications of talc and collagen-based biomaterials in different fields, such as cellular and molecular biology, and drug delivery that enhances the optical signals are needed.