2,2,2-Trifluoroethanol disrupts the triple helical structure and self-association of type I collagen

Collagen, a fibrous structural protein, is a major component of skin, tendon, bone, and other connective tissues. Collagen is one of the dominant biomaterials used for tissue engineering and drug delivery applications. 2,2,2-Trifluoroethanol (TFE) has been used as a co-solvent in the preparation of collagen based biomaterials, which are used for tissue engineering applications. However, the basic knowledge about the structural behavior of collagen in TFE is necessary for an adequate application of collagen as a carrier system. In this work, the effect of TFE on the structure and self-association of collagen has been studied in detail using different spectroscopic methods such as circular dichroism (CD), Fourier transform infrared (FTIR), and UV-Vis absorption. The results obtained from CD and FTIR suggest that collagen transform its structure from triple helix to predominantly unordered conformation with increasing concentration of TFE. Thermal melting studies reveal that the stability of collagen triple helix decreases even at low concentration of TFE. Turbidity measurements indicate that TFE, at higher concentrations, inhibits the collagen fibril formation which arises due to the self-association of collagen molecules. TFE has conventionally been known to promote the ordered structures in proteins and peptides. Destabilization of collagen triple helix by TFE is first of its kind information on the effect of TFE to disrupt the native conformation of proteins.