Microenvironmental changes in collagen/polyvinyl alcohol blends in the presence of ionic liquid: A spectroscopic analysis

Abstract

This study describes the microenvironmental changes due to various non-covalent interactions occurring in collagen/polyvinyl alcohol blends in the presence of ionic liquid, 1-butyl-3-methylimidazolium chloride, using spectroscopic techniques. These non-covalent interactions alter the hydration network of collagen. Electronic spectral analysis of collagen/polyvinyl alcohol/ionic liquid blends exhibited movement of tyrosine amino acid from the hydrophilic to hydrophobic core of collagen. Conformational studies investigating the influence of 1-butyl-3-methylimidazolium chloride on the intramolecular H-bonds revealed increased helicity packing and reorientation of H-bonds. This signifies that 1-butyl-3-methylimidazolium chloride is likely to be involved in reorienting the hydration dynamics of collagen, namely, by altering the existing and promoting formation of new intramolecular H-bonds between collagen and polyvinyl alcohol. Surface morphology of collagen/polyvinyl alcohol/ionic liquid blends revealed porous matrix, indicating 1-butyl-3-methylimidazolium chloride could act as a pore generator. This phenomenon can be employed for developing novel biomaterials with tunable porosity.