Institute for Frontier Materials, Deakin University, Geelong, Victoria 3217, Australia.
Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou 215006, P. R. China.
Langmuir. 2022 Jan 11;38(1):50-61. doi: 10.1021/acs.langmuir.1c01312. Epub 2021 Dec 28.
Functionalization of silk fibroin hydrogel with antimicrobial activity is essential for promoting the applications of this excellent biomaterial. In this work, a simple approach based on electrostatic interaction is adopted to produce antimicrobial silk hydrogel containing an antimicrobial peptide (AMP), polymyxin B, an important last-line antibiotic to treat multidrug-resistant bacterial superbugs. The polycationic property of this peptide and the negative charge of silk fibroin lead to strong interactions between them, as demonstrated by changes in nanofibril structure, gelation kinetics, ζ-potential, fluorescence emission, and rheological properties of the gel. The hydrogels loaded with polymyxin B demonstrated antimicrobial activity against two Gram-negative bacterial strains. A combination of the results from the different characterizations suggests that the optimal molar ratio of polymyxin B to silk fibroin is 1:2.5. As most AMPs are cationic, this electrostatic approach is suitable for the straightforward functionalization of inert silk hydrogel with other AMPs.
赋予丝素水凝胶抗菌活性对于促进这种优异生物材料的应用至关重要。在这项工作中，采用了一种基于静电相互作用的简单方法，制备了含有抗菌肽（AMP）、多粘菌素 B 的抗菌丝素水凝胶。多粘菌素 B 是一种重要的最后一线抗生素，用于治疗多药耐药性超级细菌。该肽的正电性和丝素纤维蛋白的负电荷导致它们之间的强烈相互作用，这可以通过纳米纤维结构、凝胶动力学、ζ-电位、荧光发射和凝胶流变性质的变化来证明。负载多粘菌素 B 的水凝胶对两种革兰氏阴性菌表现出抗菌活性。不同特性的结果表明，多粘菌素 B 与丝素纤维蛋白的最佳摩尔比为 1:2.5。由于大多数 AMP 是阳离子的，因此这种静电方法适合于将其他 AMP 简单地功能化到惰性丝素水凝胶上。
