Egg Albumin as a Template for Bio-Materials

Egg albumin a crystalline protein is currently treated as a waste from food industry. Its current applications are limited because of its crystalline nature. The ratio of ordered to disordered regions in a protein determines its physical properties. It is possible to decrease this ratio in other words increase the disordered regions by using bulky side chain groups (BSG). This can be accomplished by functionalizing the amino and carboxylic groups present in egg albumin with BSG. Here, we have functionalized egg albumin (EA) with BSG (a) ethyl vinyl sulfone (EVS) and (b) Acrylic acid through a simple “green” chemical route known as the Michael addition. The reactions are very benign and are carried out at room temperature, pH 8.0 and in water. Depending on the BSG used and the molar ratios the structure and properties of the end product varied. The resulting product has been studied using FT-IR, X-ray diffraction and Differential Scanning Calorimetry (DSC). FT-IR and X-ray diffraction studies indicated the formation of covalent bonds between BSG and the protein. The DSC results showed the decrease in crystallinity and the emergence of a Tg at a lower temperature indicative of a new amorphous phase.