Research Laboratory of Green Organic Synthesis and Polymers, Department of Chemistry, Iran University of Science and Technology, Narmak, Tehran, Iran.
School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran.
Sci Rep. 2024 Mar 29;14(1):7505. doi: 10.1038/s41598-024-58174-9.
Addressing the increasing drug resistance in pathogenic microbes, a significant threat to public health, calls for the development of innovative antibacterial agents with versatile capabilities. To enhance the antimicrobial activity of non-toxic biomaterials in this regard, this study focuses on novel, cost-effective chitosan (CS)-based hydrogels, crosslinked using gelatin (GEL), formaldehyde, and metallic salts (Ag, Cu, and Zn). These hydrogels are formed by mixing CS and GEL with formaldehyde, creating iminium ion crosslinks with metallic salts without hazardous crosslinkers. Characterization techniques like FTIR, XRD, FESEM, EDX, and rheological tests were employed. FTIR analysis showed metal ions binding to amino and hydroxyl groups on CS, enhancing hydrogelation. FESEM revealed that freeze-dried hydrogels possess a crosslinked, porous structure influenced by various metal ions. Antibacterial testing against gram-negative and gram-positive bacteria demonstrated significant bacterial growth inhibition. CS-based hydrogels containing metal ions showed reduced MIC and MBC values against Staphylococcus aureus (0.5, 8, 16 µg/mL) and Escherichia coli (1, 16, 8 µg/mL) for CS-g-GEL-Ag, CS-g-GEL-Cu, and CS-g-GEL-Zn. MTT assay results confirmed high biocompatibility (84.27%, 85.24%, 84.96% viability at 10 µg/mL) for CS-based hydrogels towards HFF-1 cells over 48 h. Therefore, due to their non-toxic nature, these CS hydrogels are promising for antibacterial applications.
针对致病微生物日益增加的耐药性问题，这是对公共卫生的重大威胁，需要开发具有多功能的创新型抗菌剂。为了提高非毒性生物材料在这方面的抗菌活性，本研究专注于新型、具有成本效益的壳聚糖（CS）基水凝胶，通过使用明胶（GEL）、甲醛和金属盐（Ag、Cu 和 Zn）交联。这些水凝胶是通过将 CS 和 GEL 与甲醛混合形成的，通过与金属盐形成亚胺离子交联，而无需使用危险的交联剂。采用傅里叶变换红外光谱（FTIR）、X 射线衍射（XRD）、场发射扫描电子显微镜（FESEM）、能量色散 X 射线光谱（EDX）和流变学测试等技术对其进行了表征。FTIR 分析表明，金属离子与 CS 上的氨基和羟基结合，增强了水凝胶的形成。FESEM 显示，冻干水凝胶具有交联的多孔结构，受各种金属离子的影响。对革兰氏阴性菌和革兰氏阳性菌的抗菌试验表明，这些水凝胶对金黄色葡萄球菌（CS-g-GEL-Ag、CS-g-GEL-Cu 和 CS-g-GEL-Zn 的 MIC 和 MBC 值分别为 0.5、8 和 16μg/mL）和大肠杆菌（MIC 和 MBC 值分别为 1、16 和 8μg/mL）的细菌生长具有显著抑制作用。MTT 测定结果证实，CS 基水凝胶对 HFF-1 细胞具有较高的生物相容性（在 10μg/mL 时的细胞活力分别为 84.27%、85.24%和 84.96%），超过 48 小时。因此，由于其无毒特性，这些 CS 水凝胶在抗菌应用方面具有广阔的应用前景。
