纳米银颗粒在模拟体液中的表面吸附特性

Surface Adsorption of Silver Nanoparticles in Simulated Body Fluids

为了了解纳米银颗粒在体内是以Ag+还是以纳米银颗粒的形式存在,本研究设计了体外模拟试验,考察纳米银颗粒在模拟体液中所发生的表面化学反应。将纳米银颗粒放在模拟体液中反应5min,30min,1h和4h,反应结束后利用ICP-MS测定溶解到模拟体液中的银离子浓度,利用TEM观察纳米银颗粒在模拟体液中的分散状态,利用XPS分析与模拟体液反应后纳米银颗粒表面化学元素组成。结果显示,纳米银颗粒与体液接触后,体液中的蛋白质会吸附到纳米银颗粒表面,绝大部分纳米银颗粒转化成覆蛋白膜的颗粒,这些覆膜颗粒可以均匀的分散在模拟体液中。只有极小一部分(小于0.01%)的纳米银颗粒会在初始阶段溶解为Ag+。这一结果说明纳米银颗粒在模拟体液中主要是以覆蛋白膜的纳米银颗粒形式存在,预示着在体内纳米银颗粒能够以颗粒形态在全身分布。这一特性可能会导致一些生物负效应的发生。

The present study was designed to investigate the chemical reactions on the surface of silver nanoparticles （SNPs） in simulated body fluids（SBFs） to make sure that if SNPs are in the form of Ag^＋ or particles in vivo. SNPs dispersed in SBFs by a shaker for 5 rain, 30 rain, 1 h and 4 h： Then the silver content in SBF was analyzed by ICP- MS, the size and state of SNPs in SBFs were observed by TEM, and the constitution of SNPs in SBFs was measured by XPS, respectively. Results show that proteins in SBFs could adsorb on the surface of most SNPs and a proteinic membrane is formed outside the nanoparticles. These SNPs with a proteinic membrane could disperse in SBFs. Only a small quantity of SNPs（〈0.01%） would dissolve to Ag^＋ in initial 30 minutes. So we suggest that silver nanoparticles could distribute systemic in the form of particles with a proteinic membrane in vivo and these characteristics must be study in vivo.