关键词: 蚕丝织物, 氧化壳聚糖, 交联改性, 抗菌织物, 释药载体

Abstract:

In order to acquire durable antibacterial silk materials, the hydroxyl of C6 site in original chitosan (CS) was selectively oxidized to the carboxyl by HNO₃/H₃PO₄-NaNO₂ mediate system and obtained the water-soluble oxidized chitosan (OCS), and then the chemical bond was formed through the amide reaction between carboxyl groups in oxidized chitosan and amino groups of silk fibroin fabric (SFF) to get antimicrobial silk fibroin materials (OCSMSF). Nuclear magnetic resonance, Scanning electron microscopy, Infrared spectroscopy and X-ray diffraction were used to test the chemical structure of OCS and OCSMSF, moreover, the mechanics, hygroscopicity and antibacterial activity of OCSMSF materials were also measured. The results suggest that the carboxylic chitosan molecules are crosslinked into SFF by the amide reaction, and the degree of crystallinity for SFF materials grafted with OCS decrease. The oxidized chitosan weight gain of 9.17% for the modified silk fabric is achieved under the condition of optimized reaction parameters, the tensile strength of grafted silk fabrics reduces slightly, whereas the moisture adsorption of the modified SFF increases 42.92%. Furthermore, the antimicrobial ratio of the grafted SFF against the tested bacteria exceedes 94%, as well as still high antibacterial activity after washing; meanwhile, a good efficiency of sustained release cactus flavonoid extract using the OCSMSF is performed. The OCS grafted silk materials have potential application prospect in antibacterial materials or carrier materials of release drug.

Key words: silk fabric, oxidized chitosan, crosslink modification, antibacterial, release carrier