Polymers Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899-8543, USA.
J Biomed Mater Res B Appl Biomater. 2011 Apr;97(1):124-31. doi: 10.1002/jbm.b.31793. Epub 2011 Feb 2.
Nanocomposites of cross-linked methacrylate polymers with silver nanoparticles have been synthesized by coupling photoinitiated free radical polymerization of dimethacrylates with in situ silver ion reduction. A polymerizable methacrylate bearing a secondary amino functional group was used to increase the solubility of the silver salt in the hydrophobic resin system. Fourier transform infrared spectroscopy (FTIR) revealed that the silver ion reduction had no significant effect on the degree of vinyl conversion of the methacrylate. X-ray photoelectron spectroscopy (XPS) measurements showed an increased silver concentration at the composite surface compared to the expected concentration based on the total amount of silver salt added. Furthermore, the surface silver concentration leveled off when the silver salt mass fractions were 0.08% or greater. Composites with low concentrations of silver salt (< 0.08% by mass) exhibited comparable mechanical properties to those containing no silver. Transmission electron microscopy (TEM) confirmed that the silver nanoparticles formed within the polymer matrix were nanocrystalline in nature and primarily ≈ 3 nm in diameter, with some large particle aggregates. Composites containing silver nanoparticles were shown to reduce bacterial colonization with as little as 0.03% (by mass) silver salt, while additional amounts of silver salt did not further decrease their surface colonization. With a substantial effect on bacterial growth and minimal effects on mechanical properties, the in situ formation of silver nanoparticles within methacrylate materials is a promising technique for synthesizing antibacterial nanocomposites for biomedical applications.
通过将双甲基丙烯酸酯的光引发自由基聚合与原位银离子还原偶联，合成了交联甲基丙烯酸聚合物与银纳米粒子的纳米复合材料。使用带有仲氨基官能团的可聚合甲基丙烯酯来增加银盐在疏水性树脂体系中的溶解度。傅里叶变换红外光谱（FTIR）表明，银离子还原对甲基丙烯酯的乙烯基转化率没有显著影响。X 射线光电子能谱（XPS）测量表明，与根据添加的总银盐量预期的浓度相比，复合材料表面的银浓度增加。此外，当银盐质量分数为 0.08%或更高时，表面银浓度趋于稳定。银盐浓度低（质量分数<0.08%）的复合材料的机械性能与不含银的复合材料相当。透射电子显微镜（TEM）证实，在聚合物基质内形成的银纳米粒子本质上是纳米晶，直径主要约为 3nm，存在一些大的颗粒聚集体。含有银纳米粒子的复合材料显示出，只要含有 0.03%（质量分数）的银盐就可以减少细菌定植，而额外的银盐含量不会进一步降低其表面定植。由于对细菌生长有显著影响，对机械性能的影响最小，因此在甲基丙烯酸酯材料中原位形成银纳米粒子是一种有前途的用于合成抗菌纳米复合材料的技术，可用于生物医学应用。
