Research Center for Biomedical Implants and Microsurgery Devices, Taipei Medical University, Taipei, Taiwan.
Nanotechnology. 2012 Jun 29;23(25):255103. doi: 10.1088/0957-4484/23/25/255103. Epub 2012 May 31.
Despite the fact that polystyrene (PS) spheres have been developed as polymeric carriers or matrices for various biomedical applications, the synthesis of PS spheres is time-consuming. This work describes the fabrication of a uniform PS sphere, coated with silver nanoparticles (Ag-PS), by simultaneous photoinduced polymerization and reduction fabricated using x-rays in aqueous solution without any initiator. The solution contains only styrene, silver ions (Ag(+)), and poly(vinyl pyrrolidone) (PVP) as a stabilizer. The proposed mechanism of the formation of the Ag-PS nanocomposite spheres involves the generation of radicals in the aqueous solution to induce PS polymerization and the reduction of Ag. The distribution of the sizes of the core PS spheres in the Ag-PS nanocomposite spheres was systematically examined as a function of irradiation time, concentration of styrene, and amount of PVP. Ag-PS nanocomposite spheres exhibit antimicrobial activity against bacteria (Escherichia coli and Staphylococcus aureus). Additionally, the cationic (vinylbenzyl)trimethylammonium (TMA) monomer was photopolymerized to form positively charged TMA-PS spheres as gene carriers with uniquely low cytotoxicity. Given these design advantages, the method proposed herein is simpler than typical approaches for synthesizing PS spheres with functionalized groups and PS spheres coated with Ag nanoparticles.
尽管聚苯乙烯（PS）球已被开发为各种生物医学应用的聚合物载体或基质，但 PS 球的合成过程耗时较长。本工作描述了在水溶液中使用 X 射线在无引发剂的情况下同时进行光引发聚合和还原反应，制备涂覆有银纳米粒子（Ag-PS）的均匀 PS 球。该溶液仅包含苯乙烯、银离子（Ag(+)）和作为稳定剂的聚乙烯吡咯烷酮（PVP）。Ag-PS 纳米复合材料球形成的拟议机制涉及在水溶液中产生自由基以引发 PS 聚合和还原 Ag。系统地研究了作为辐照时间、苯乙烯浓度和 PVP 用量函数的核 PS 球在 Ag-PS 纳米复合材料球中的尺寸分布。Ag-PS 纳米复合材料球对细菌（大肠杆菌和金黄色葡萄球菌）表现出抗菌活性。此外，阳离子（乙烯基苄基）三甲基铵（TMA）单体被光聚合以形成带正电荷的 TMA-PS 球作为基因载体，具有独特的低细胞毒性。鉴于这些设计优势，与具有官能团的 PS 球和涂覆有 Ag 纳米粒子的 PS 球的典型合成方法相比，本文提出的方法更简单。
