Application of statistical method to evaluate immobilization variables of trypsin entrapped with sol-gel method

Bioimmobilization with sol-gel method is a complicate system,involving many parameters that can affect sol-gel structure andimmobilized biomolecules activity. In this study, trypsin, a modelenzyme, was entrapped into sol-gel glasses produced fromtetraethoxysilane (TEOS) and water to study the relationshipsbetween the immobilization parameters, namely ratio of water toTEOS, volume of poly (ethylene glycol) (PEG), concentration ofbuffer solution, pH of buffer solution by using statistical methods.Two regression equations and analysis of variance (ANOVA) wereobtained with the entrapped enzyme activity and enzyme loadingyield as the response values, respectively. Statistical calculationsshowed that the effects of the four variables on the entrappedenzyme activity and enzyme loading yield were different. Entrappedtrypsin activity (35.6%) and trypsin loading yield (68.3%) wereobtained by using optimized immobilization conditions. The resultsof this study may help to manipulate the properties of sol-gel to gethigh immobilization efficiency.