Carboxymethyl chitosan (CMCh) is a water-soluble chitosan derivative and it has been widely used in biomedical applications due to its unique properties. Modification of CMCh by graft copolymerization with different monomers is done in order to enhance its applications. Graft copolymerization of styrene (S) onto CMCh using ammonium persulfate (APS) as initiator was successfully done with optimization of grafting parameters. The new materials were prepared in nano size. The antibacterial activities against Streptococcus pneumonia (RCMB 010010), Staphylococcus aureus (RCMB 010028) as Gram-positive and Escherichia coli (RCMB 010052) as Gram-negative bacteria and antifungal activity against Aspergillus fumigates (RCMB 02568), Candida albicans (RCMB 05036), Syncephalastrum racemosum (RCMB 05922), and Geotricum candidum (RCMB 05097) were examined using the diffusion agar technique. Also, the cytotoxicity effect against mammalian cell lines (MCF-7cells (human breast cancer) and HTC-116 (colon carcinoma)) was evaluated. The obtained data proved that grafted carboxymethyl chitosan with styrene (CMCh-g-S) shows better antimicrobial activities, while parent carboxymethyl chitosan showed higher activity than new grafted materials. Also the nano scaled grafted CMCh showed higher activities than grafted carboxymetyl chitosan in macro scale.

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苯乙烯接枝羧甲基壳聚糖及其生物学应用

羧甲基壳聚糖 (CMCh) 是一种水溶性壳聚糖衍生物，由于其独特的性质已广泛应用于生物医学领域。通过与不同单体的接枝共聚对CMCh进行改性以增强其应用。使用过硫酸铵 (APS) 作为引发剂，苯乙烯 (S) 在 CMCh 上的接枝共聚成功完成，并优化了接枝参数。新材料制备成纳米尺寸。对肺炎链球菌 (RCMB 010010)、金黄色葡萄球菌 (RCMB 010028) 革兰氏阳性菌和大肠杆菌 (RCMB 010052) 革兰氏阴性菌的抗菌活性和对烟曲霉 (RCMB 02568)、念珠菌 (Candida) 的抗真菌活性 (RCMB 02568) , Syncephalastrum racemosum (RCMB 05922), 使用扩散琼脂技术检查和白地霉（RCMB 05097）。此外，还评估了对哺乳动物细胞系（MCF-7 细胞（人乳腺癌）和 HTC-116（结肠癌））的细胞毒性作用。所得数据证明，与苯乙烯接枝的羧甲基壳聚糖（CMCh-gS）显示出更好的抗菌活性，而母体羧甲基壳聚糖显示出比新接枝材料更高的活性。此外，在宏观尺度上，纳米级接枝的 CMCh 显示出比接枝羧甲基壳聚糖更高的活性。而母体羧甲基壳聚糖显示出比新接枝材料更高的活性。此外，在宏观尺度上，纳米级接枝的 CMCh 显示出比接枝羧甲基壳聚糖更高的活性。而母体羧甲基壳聚糖显示出比新接枝材料更高的活性。此外，在宏观尺度上，纳米级接枝的 CMCh 显示出比接枝羧甲基壳聚糖更高的活性。