Soule Logan D, Pajares Chomorro Natalia, Chuong Kayla, Mellott Nathan, Hammer Neal, Hankenson Kurt D, Chatzistavrou Xanthippi
Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States.
Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48823, United States.
ACS Biomater Sci Eng. 2020 Oct 12;6(10):5549-5562. doi: 10.1021/acsbiomaterials.0c01140. Epub 2020 Sep 8.
Although metallic alloys commonly used as prosthetics are durable and mechanically strong, they are often bioinert and lack antibacterial properties. Implementing a bioactive glass material with antibacterial properties as a coating on a metallic substrate provides mechanical strength and bioactivity, as well as antibacterial properties. Many coating methods have been extensively investigated; however, most of them can be expensive, are difficult to scale up, or do not form thin films, which could prevent their translation to clinical practice. The formation of thin films by spin-coating multi-component solution-gelation (sol-gel)-derived glass with antibacterial and bioactive properties has not been achieved previously. For this study, stainless steel 316L substrates were spin-coated with a sol-gel-derived bioactive and antibacterial glass coating in SiO 58.3-PO 7.1-CaO 25.6-AlO 5.4-AgO 2.1-NaO 1.5 wt% system (Ag-BG). A sol-gel processing condition that avoids elemental separation upon spin-coating when sintering happens at below the calcination temperature (500 °C) has been developed. This work demonstrates that silver reduction occurs when the concentrations of other cations such as Ca and Na in the solution increase. Increasing the stirring duration time prior to the increase of cations, Ag ions are stabilized by aluminum tetrahedra, and their reduction to metallic silver does not occur. This study also shows that large dilution ratios (water:tetraethyl orthosilicate) greater than 25:1, accompanied by long stirring durations, produce morphologically homogeneous coatings. Using this strategy, thin films were formed with antibacterial properties against methicillin-resistant (MRSA) biofilm and biological responses that promote eukaryotic cell adhesion and proliferation. In total, the improved synthesis strategy opens new avenues for the development of novel bioactive and antibacterial thin-film coatings, as it reveals the processing characteristics that control the physicochemical and morphological properties of the formed films.
尽管通常用作假肢的金属合金耐用且机械强度高，但它们往往具有生物惰性且缺乏抗菌性能。在金属基底上涂覆具有抗菌性能的生物活性玻璃材料，可提供机械强度、生物活性以及抗菌性能。许多涂覆方法已得到广泛研究；然而，其中大多数可能成本高昂、难以扩大规模，或者无法形成薄膜，这可能会阻碍它们转化为临床应用。通过旋涂具有抗菌和生物活性的多组分溶液 - 凝胶（溶胶 - 凝胶）衍生玻璃来形成薄膜，此前尚未实现。在本研究中，对316L不锈钢基底进行旋涂，使其表面形成SiO 58.3 - PO 7.1 - CaO 25.6 - AlO 5.4 - AgO 2.1 - NaO 1.5 wt%体系（Ag - BG）的溶胶 - 凝胶衍生生物活性抗菌玻璃涂层。已开发出一种溶胶 - 凝胶加工条件，当烧结在低于煅烧温度（500°C）下进行时，可避免旋涂时元素分离。这项工作表明，当溶液中Ca和Na等其他阳离子浓度增加时，会发生银的还原。在阳离子增加之前延长搅拌持续时间，Ag离子会被四面体铝稳定，不会还原为金属银。该研究还表明，大于25:1的大稀释比（水：原硅酸四乙酯），伴随着长时间搅拌，可产生形态均匀的涂层。使用这种策略，形成了对耐甲氧西林金黄色葡萄球菌（MRSA）生物膜具有抗菌性能以及促进真核细胞粘附和增殖的生物反应的薄膜。总的来说，这种改进的合成策略为新型生物活性和抗菌薄膜涂层的开发开辟了新途径,因为它揭示了控制所形成薄膜的物理化学和形态特性的加工特征。
