二氧化钛纳米线阵列富集与内部萃取电喷雾电离质谱联用检测大豆磷脂

Determination of Phospholipids in Soybean by Titanium Dioxide Nanowires Array Enrichment Combined with Internal Extractive Electrospray Ionization Mass Spectrometry

通过水热合成方法,在掺杂F的SnO_2导电玻璃(FTO)基底上制备了TiO_2纳米线阵列结构,并与内部萃取电喷雾电离质谱法(i EESI-MS)联用,实现了大豆中磷脂类物质的选择性富集和直接质谱分析。系统考察了三氟乙酸(TFA)-甲醇比例、吸附时间、洗脱剂组成以及洗脱流速对大豆中磷脂类物质检测的影响。结果表明,在萃取液为2%(V/V) TFA-甲醇、吸附时间为60 s、洗脱剂为1. 5%(V/V)氨水-甲醇、洗脱流速7μL/min的条件下,可以获得最佳的磷脂类成分信号。在优化条件下,从大豆研磨液中检测到了18种磷脂类成分,基于此可利用主成分分析(PCA)对产自黑龙江、江苏、四川、山东和河南的大豆进行初步区分。本方法对大豆磷脂定量分析的检出限(S/N≥3)为0.01μg/L,相对标准偏差(RSD,n=3)为1.6%～6.5%,表明本方法具有较高的检测灵敏度。此外,本方法还可用于对大豆商品油品质进行快速准确筛查。本方法具有样品耗量少、分析速度快、操作简便等优势,有望为大豆中磷脂类物质的快速检测提供一种新方法。

Titanium dioxide(TiO 2)nanowires array prepared on the fluorine-doped tin oxide(FTO)substrate by the hydrothermal synthesis method was combined with internal extractive electrospray ionization mass spectrometry(iEESI-MS),allowing selective enrichment and direct analysis of the phospholipids from soybean.The experimental parameters including ratio of trifluoroacetic acid(TFA)in methanol,adsorption time,composition,and flow rate of eluent were investigated.The results showed that the optimal signal of phospholipids was obtained under the optimized conditions such as the extraction solution of 2%(V/V)TFA in methanol,adsorption time of 60 s,eluent of 1.5%(V/V)ammonia in methanol and flow rate of 7μL/min.A total of 18 kinds of phospholipids were detected from the grinding soybean solution.Based on these components,the soybeans from Heilongjiang,Jiangsu,Sichuan,Shandong and Henan were preliminarily separated by principal component analysis(PCA).The limits of detection(S/N≥3)were 0.01μg/L and the relative standard deviations(RSDs,n=3)were 1.6%-6.5%,showing high sensitivity in the quantitative analysis of phospholipids from soybean.Besides,accurate and rapid screening of the quality of commercial soybean oil was also achieved.This method was featured by less sample consumption,rapid analysis and simple operation,and could be used for direct and rapid detection of phospholipids in soybean.