Applications Of Silk Fibroin Hydrogel In Enzyme-Based Biocomputing And Organic Catalysis

As a typical soft material,silk fibroin hydrogel has played an important role in many fields in recent years.With more and more in-depth understandings,silk fibroin hydrogel has attracted a growing interest of many researchers due to its characteristics such as excellent biocompatibility and easy degradation,and thus setting off a vigorous exploration.In combination with the enzymatical biocatalysis,this paper chiefly studies the applications of silk fibroin hydrogel in biocomputing and industrial catalysis.The main research results are as follows:1.Based on the mechanism of chemical gelatinization of silk fibroin,we proposed a simple and effective Boolean logic operation system with dual-readout by combining different biological enzymes as inputs.Experimental results proved that our logic-gate can successfully implement AND,INHIBIT and AND-INHIBIT logical operations.The advantage of this strategy is that invisible molecular events in aqueous media could be translated into quick response of sol-gel transition of silk fibroin through diverse enzymatic cascade reactions without any signal "crosstalk".Components in the system can be judged by observing the state and UV-vis absorption changes.We believe that such logical computing network will have the opportunity to be used in medical preliminary diagnosis and treatment.2.In order to break through the functional limitations of natural enzymes when used in the industrial environments,we use silk fibroin as a unique sol-gel protective matrix to prevent them from inactivating rapidly due to structural damage once exposed to non-aqueous reaction media.This porous silk fibroin hydrogel can not only retain the catalytic ability of the enzyme,but also provide permeable channels,which are beneficial to catalytic reactions.All results show that immobilized enzymes on silk fibroin hydrogels have much higher activity and stability in different organic solvents than free natural enzymes.Besides,horseradish peroxidase,which entrapped in silk fibroin hydrogel,remains more than 50%catalytic ability,indicating certain reusability as well.In addition,this enzyme immobilization strategy can be extended to other biocatalysts,which we think is of great significance for practical industrial applications.