酶消解-单颗粒电感耦合等离子体质谱法测定农产品中纳米铂颗粒

Determination of Platinum Nanoparticles in Agricultural Products by Enzyme Digestion Combined Single Particle Inductively Coupled Plasma Mass Spectrometry

铂纳米颗粒在汽车行业中被广泛用作汽车尾气催化剂。随着铂纳米颗粒在工业生产中的广泛应用,它在环境中广泛分布并可能从植物累积进入食物链中。因此,建立一种在农产品中的定量分析方法是至关重要的。以酶消解的前处理方法结合单颗粒-电感耦合等离子体质谱法(Single particle ICP-MS,SP-ICP-MS)测定农产品中纳米铂颗粒(PtNPs)粒径分布及颗粒数量浓度。通过优化前处理提取条件,当Macerozyme R-10酶为10 mg、柠檬酸缓冲溶液浓度为5 mmol/L、提取时间36 h时,农产品中PtNPs提取效果较高。PtNPs粒径检出限为20 nm,颗粒浓度检出限为5×10^(5) particle/L,铂颗粒浓度回收率在(81±3)%~(91±4)%,加标后平均粒径(41±3)~(47±2)nm,与50 nm PtNPs标准溶液粒径接近。方法操作简单、检出限低、准确度高,适用于农产品中PtNPs定量分析,为客观评价农产品铂纳米毒性效应提供可靠的分析技术。

Platinum nanoparticles are widely used as catalysts for automobile exhaust in the automotive industry.With the wide application of platinum nanoparticles in industrial production,platinum nanoparticles are widely distributed in the environment and may accumulate from plants into the food chain.Therefore,it is very important to establish a quantitative analysis method in agricultural products.An enzymatic digestion method combined with single particle ICP-MS(SP-ICP-MS)was established for the determination of platinum nanoparticle(PtNPs)in agricultural products in this paper.The extraction parameters of PtNPs in samples were optimized,10 mg Macerozyme R-10 enzyme was dispersed in 10 mL 5 mmol/L which was spiked in 20 mg sample and then shaken for 36 h at 37℃.The detection limit of size and particle concentration was 25 nm and 5×10^(5) particle/L,respectively.The recovery rate of particle concentration for PtNPs in agricultural products was in the range of(81±3)%—(91±4)%.The average size of PtNPs in sample spiked with standard sample of 50 nm PtNPs was(41±3)—(47±2)nm,which was accordance with the value of TEM.This proposed enzymatic digestion method combined with SP-ICP-MS method for the detection of PtNPs in agricultural products is with the features of easy operation,low limit of detection and high accuracy,which could provide a reliable analysis technique for the evaluation of Pt nano-toxicity effect of agricultural products.