Effect of the Method of Nanocomplex Synthesis on the Proteolytic Activity of Chymotrypsin Immobilized on Silver Nanoparticles

Two methods for the synthesis of hybrid organic-inorganic nanocomplexes comprising chymotrypsin and silver nanoparticles have been developed based on the chemical reduction of silver nitrate by sodium borohydride. In the first method, the enzyme is added to the reaction mixture simultaneously with other reagents. In the second method, it is added to the reaction mixture at certain intervals after the start of the reduction reaction. Chymotrypsin immobilized on nanocomplexes stabilizes silver nanoparticles. As compared to the native enzyme, the immobilized enzyme prepared by the both methods exhibits an increased proteolytic activity in acidic and strongly alkaline media. At the same time, chymotrypsin immobilized on silver nanoparticles by the second method exhibits the highest level of proteolytic activity.