Rapid Kinetics of Size and pH-Dependent Dissolution and Aggregation of Silver Nanoparticles in Simulated Gastric Fluid.
Rapid Kinetics of Size and pH-Dependent Dissolution and Aggregation of Silver Nanoparticles in Simulated Gastric Fluid.
复制标题
DOI：
10.1021/acs.jpcc.5b03634
复制
发表时间：
2015-09-03
期刊：
影响因子：
--
通讯作者：
Ault AP
中科院分区：
文献类型：
--
作者：
Axson JL;Stark DI;Bondy AL;Capracotta SS;Maynard AD;Philbert MA;Bergin IL;Ault AP
由于银纳米颗粒（AgNP）被用于广泛的商业产品中，并且可以通过口服暴露进入人体，因此重要的是理解在胃肠道（GI）条件下导致纳米颗粒尺寸变化的基本物理和化学过程。在模拟胃液（SGF）中使用30秒分辨率的纳米颗粒跟踪分析在17分钟的时间内观察到快速AgNP生长，以探索作为pH（SGF在pH 2、3.5、4.5和5下）、尺寸（20和110 nm AgNP）和纳米颗粒涂层（柠檬酸盐和PVP）的函数的快速动力学。在每个pH值下观察到20 nm AgNP的生长，随着pH值的增加，生长速率降低，动力学从二阶变为一阶。110 nm的AgNP在pH ≤3.5时显示出生长，在较高pH下没有观察到生长。这种行为可以通过在酸性环境中产生Ag+来解释，Ag+与Cl−沉淀，导致颗粒生长并通过降低溶液中的静电排斥促进颗粒聚集。这些结果强调了需要进一步了解摄入后AgNPs的初始大小，理化性质和动力学的重要性，以评估潜在的毒性。
As silver nanoparticles (AgNPs) are used in a wide array of commercial products and can enter the human body through oral exposure, it is important to understand the fundamental physical and chemical processes leading to changes in nanoparticle size under the conditions of the gastrointestinal (GI) tract. Rapid AgNP growth was observed using nanoparticle tracking analysis with 30 s resolution over a period of 17 min in simulated gastric fluid (SGF) to explore rapid kinetics as a function of pH (SGF at pH 2, 3.5, 4.5 and 5), size (20 and 110 nm AgNPs), and nanoparticle coating (citrate and PVP). Growth was observed for 20 nm AgNP at each pH, decreasing in rate with increasing pH, with the kinetics shifting from second-order to first-order. The 110 nm AgNP showed growth at ≤3.5 pH, with no growth observed at higher pH. This behavior can be explained by the generation of Ag+ in acidic environments, which precipitates with Cl−, leading to particle growth and facilitating particle aggregation by decreasing their electrostatic repulsion in solution. These results highlight the need to further understand the importance of initial size, physicochemical properties, and kinetics of AgNPs after ingestion to assess potential toxicity.