Fabrication Of Antibacterial Wool Surfaces Via Layer-by-layer Electrostatic Self-assembly Immobilization Of Lysozymes

As an excellent natural antibacterial agent with high specificity, mild reaction conditions, high catalytic efficiency and so on, lysozymes are widely applied in food, madicine, bioengineering, cosmetics fields and so on, but it is still in the start-up periods in textiles.Lay-by-lay electrostatic self-assembly technology is a new method that builds nanometer thin films on the substrate surface using electrostatic force. This method can protect the secondary structure and biological stability of biological macromolecules, so many biological molecules can be immobilized using this method. In this study, as the condition of the amphoteric character under wool. The charge of wool surface will be changed by changing the pH value of buffer solution, lysozyme will be fixed on the surface of wool fabric, and using the anion of PSS to achieve multi-layer assembly of lysozyme. After self-assembly processing, Thesis investigates the morphological changes of wool, the changes of Surface potential on wool, changes in protein content. And the assembly conditions such as pH, temperature, polymer concentration effects on the experimental results are also studied. At the same time, pH stability, thermal stability, storage stability are studied between the free enzyme and immobilized enzyme, and the wash-resistant stability and operational stability are studied between assembled enzyme and adsorbed enzyme.Experimental results show that after 10 times treated by the electrostatic self-assembly method, part of the groove on the surface of wool fabric is filled with granular material existence; after assembly, with the increasing of the assembly layers, the potential on wool surface appears a "layers of alternating oscillation" phenomenon; staining experiments show that the surface potential of wool achieves the reversal potential between positive and negative; Dyed with Coomassie brilliant blue after assembly, and double-beam UV spectrophotometer test results prove the number of sample protein content increase with the number of assembly; Wool has good antibacterial activity after assembly. Through the analysis of the experimental factors,we can know, pH value of 4 is the worst, pH value of 7 is the best, assembled at 40℃,the effect is best, polymer concentration and dipping time did not affect the experimental results significantly. Through electrostatic self-assembly processing, the immobilized enzyme has good pH stability, thermal stability and storage stability, while Washing stability of assembly enzyme is a lot better than the adsorption enzym.