基于单颗粒电感耦合等离子体质谱法测定环境基质水样中纳米银颗粒

采用单颗粒电感耦合等离子体质谱法(SP-ICP-MS)同时测定环境水样中纳米银颗粒(AgNPs)的颗粒浓度、质量浓度和粒径分布,并考察了溶液的pH值、溶解性有机质(DOM)浓度以及离子强度等对AgNPs测定的影响。结果表明:SP-ICP-MS方法对60 nm AgNPs标准溶液的测定结果与标准值一致,准确性较好;pH值(5.0~7.0)、离子强度(≤1 mmol/L)和DOM浓度(≤30 mg/L)对测定结果影响较小;当溶液的pH值≤5.0或离子强度>1 mmol/L时,AgNPs的颗粒浓度和粒径随pH值的下降或离子强度的增强而减小。采用SP-ICP-MS方法测定河水、染料废水、养殖废水3种水样中AgNPs的加标回收率分别为98.1%、83.3%和93.3%,表明该方法在合适的基质条件下可用于快速准确测定环境水样中AgNPs的颗粒浓度、质量浓度和粒径分布。

Determination of Nano Silver Particles in Environmental Matrix Water by Single Particle Inductively Coupled Plasma Mass Spectrometry

A single particle inductively coupled plasma mass spectrometric(SP-ICP-MS) method was developed for simultaneous determination of the particle concentration,mass concentration and particle size distribution of nano silver particles(AgNPs) in environmental water samples.Effects of pH,dissolved organic matter(DOM) concentration and ionic strength of the solution on AgNPs were also investigated.A 60 nm AgNPs standard solution was determined by SP-ICP-MS with good accuracy,which results were consistent with the certified values.Impacts on the determine results were low in the conditions of pH value within 5 to 7,ionic strength not more than mmol/L and DOM concentration not larger than 30 mg/L.When pH value of the solution was not more than 5 or the ionic strength was larger than 1,the particle concentration and the particle size decreased with decreasing pH or increasing ionic strength.The method was applied to the detection of AgNPs in three actual water samples of river water,dye wastewater,and aquaculture wastewater,with the spiked recoveries for AgNPs of 98.1%,83.3% and 93.3%,respectively.Results indicated that the SP-ICP-MS method could be used for quick and accurate determination of the particle concentration,mass concentration,and particle size distribution of AgNPs in environmental water samples under appropriate matrix conditions.