Gao Ya, Zhang Wei, Cheng Yan Fang, Cao Yang, Xu Zhigang, Xu Li Qun, Kang Yuejun, Xue Peng
School of Materials and Energy, Southwest University, Chongqing 400715, China.
Biomater Sci. 2021 Mar 21;9(6):2244-2254. doi: 10.1039/d0bm02136a. Epub 2021 Jan 29.
Skin infections caused by pathogens, including bacteria, fungi and viruses, are difficult to completely eliminate through standard topical administration, owing to the restricted drug permeation into the epidermis layer. Herein, we developed a poly(ethylene glycol) diacrylate (PEGDA) microneedle patch with surface coating of a nanosilver (NS) encapsulated gelatin/sucrose film for antibacterial applications, by virtue of enhanced skin permeation by microneedle penetration and efficient drug delivery through rapid film dissolving. NS was facilely synthesized through a green process based on the bioinspired crystallization of ionic state silver in the presence of a silk fibroin (SF) template. A gelatin/sucrose polymeric film encapsulating NS was dressed on the surface of the mold cavity, and film-coated PEGDA (PEGDA/film-NS) microneedles were subsequently fabricated through standard ultraviolet (UV) light-induced polymerization. To demonstrate their advantages for therapeutic applications, the physicochemical properties of the as-developed microneedles were characterized in terms of their morphology, composition, mechanical strength, etc. Moreover, rapid NS release from PEGDA@film-NS microneedles driven by the aqueous environment was demonstrated under physiological conditions. Additionally, such film-coated microneedles exhibited good mechanical strength for skin penetration, and their antibacterial activity against Gram-positive bacteria (Staphylococcus epidermidis and Staphylococcus aureus) as well as Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) was verified using bacterial suspension in vitro. Altogether, such a minimally invasive strategy exhibited good potential for realizing a broad-spectrum antibacterial effect, which may provide a practical methodology for the management of polymicrobial skin infection during clinical trials.
由包括细菌、真菌和病毒在内的病原体引起的皮肤感染，由于药物渗透到表皮层受到限制，难以通过标准的局部给药完全消除。在此，我们开发了一种聚（乙二醇）二丙烯酸酯（PEGDA）微针贴片，其表面涂覆有纳米银（NS）包裹的明胶/蔗糖膜用于抗菌应用，这得益于微针穿透增强了皮肤渗透性以及通过快速的膜溶解实现了高效的药物递送。NS是通过基于丝素蛋白（SF）模板在离子态银的仿生结晶的绿色工艺简便合成的。将包裹NS的明胶/蔗糖聚合物膜覆盖在模具腔表面，随后通过标准的紫外（UV）光诱导聚合制备膜包被的PEGDA（PEGDA/膜-NS）微针。为了证明它们在治疗应用中的优势，对所开发微针的物理化学性质进行了形态、组成、机械强度等方面的表征。此外，在生理条件下证明了PEGDA@膜-NS微针在水环境驱动下能快速释放NS。另外，这种膜包被的微针表现出良好的皮肤穿透机械强度，并且使用细菌悬液在体外验证了它们对革兰氏阳性菌（表皮葡萄球菌和金黄色葡萄球菌）以及革兰氏阴性菌（大肠杆菌和铜绿假单胞菌）的抗菌活性。总之，这种微创策略在实现广谱抗菌效果方面展现出良好的潜力，这可能为临床试验期间多重微生物皮肤感染的管理提供一种实用方法。
