optimization of sericin removal from tusser silk by autoclaving

Abstract

Silk is an important biomaterial for tissue engineering purposes due to its improved mechanical and biological properties. The natural fiber has two major components – the structural centre protein chain called fibroin and the outer glue like covering fiber called sericin. It has been well documented that sericin has the immunogenic properties in animal and human physiological system and so the silk is used only after the sericin is removed thus improving the mechanical and biological properties of silk. Removing sericin from silk is called degumming i.e. “removing the gum”. It should be done carefully in a way that the fibroin is not damaged. Sericin is removed by using a base such as anhydrous sodium carbonate as well as autoclaving by using water under pressure. By varying one parameter and keeping the other two fixed we find out the optimum temperature, time, concentration as well as pressure to degum silk such that the sericin is removed optimally and the structural integrity of silk is not lost. By SEM analysis the morphological characteristics of degummed silk was studied.70 degree celsius, 0.02M Na2CO3 and 35 minutes for degumming using Na2CO3 and 15psi, 121 degree celsius, 15 minutes were found to be the optimum parameters for degumming.