Herein, we report on the formation of cross-linked antimicrobial peptide-loaded microgel multilayers. Poly(ethyl acrylate-co-methacrylic acid) microgels were synthesized and functionalized with biotin to enable the formation of microgel multilayers cross-linked with avidin. Microgel functionalization and avidin cross-linking were verified with infrared spectroscopy, dynamic light scattering, and z-potential measurements, while multilayer formation (up to four layers) was studied with null ellipsometry and quartz crystal microbalance with dissipation (QCM-D). Incorporation of the antimicrobial peptide KYE28 (KYEITTIHNLFRKLTHRLFRRNFGYTLR) into the microgel multilayers was achieved either in one shot after multilayer formation or through addition after each microgel layer deposition. The latter was found to strongly promote peptide incorporation. Further, antimicrobial properties of the peptide-loaded microgel multilayers against Escherichia coli were investigated and compared to those of a peptide-loaded microgel monolayer. Results showed a more pronounced suppression in bacterial viability in suspension for the microgel multilayers. Correspondingly, LIVE/DEAD staining showed promoted disruption of adhered bacteria for the KYE28-loaded multilayers. Taken together, cross-linked microgel multilayers thus show promise as high load surface coatings for antimicrobial peptides.

中文翻译：

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抗生物素蛋白-生物素交联的微凝胶多层作为抗菌肽的载体。

在此，我们报道了交联的抗微生物肽负载的微凝胶多层的形成。聚（丙烯酸乙酯-共合成了（甲基丙烯酸）微凝胶并用生物素功能化，以形成与抗生物素蛋白交联的微凝胶多层。通过红外光谱，动态光散射和z电位测量验证了微凝胶功能化和抗生物素蛋白的交联，同时使用零椭偏法和带耗散的石英晶体微天平（QCM-D）研究了多层结构（最多四层）。将抗微生物肽KYE28（KYEITTIHNLFRKLTHRLFRRNFGYTLR）掺入微凝胶多层中，既可以在多层形成后一次注射，也可以在每次微凝胶层沉积后通过添加而实现。发现后者强烈促进肽掺入。此外，载有肽的微凝胶多层膜对大肠杆菌的抗菌特性进行了研究，并与载有肽的微凝胶单层膜进行了比较。结果显示，对于微凝胶多层膜，悬浮液中细菌生存力的抑制作用更为明显。相应地，LIVE / DEAD染色显示，对于装载KYE28的多层膜，粘附细菌的破坏作用得到了促进。综上所述，交联的微凝胶多层因此显示出作为抗微生物肽的高负荷表面涂层的希望。