离子色谱-质谱联用(IC/MS)法检测葡萄酒样品中的柠檬酸

Determination of citric acid in wine samples by ion chromatography-electrospray ionization tandem mass spectrometry (IC/MS)

中文关键词:  柠檬酸  离子色谱串联质谱法  葡萄酒

英文关键词:citric acid  IC/ESI-MS  wine

中文摘要:

      目的 建立了离子色谱-质谱联用技术测定葡萄酒样品中柠檬酸的分析方法。方法 以高容量、强亲水性的IonPac AS20型阴离子交换柱为分析柱, EGC在线产生梯度浓度KOH为淋洗液, 淋洗液经捕获柱、抑制器成水后将样品带入质谱检测器。ESI-SIM监测模式监控柠檬酸根离子(m/z=191), 并以峰面积进行定量。结果 该方法对柠檬酸的检出限(S/N=3)为17.6 μg/L, 且柠檬酸浓度在50~1000 μg/L范围内具有良好的线性, 线性相关系数r=0.9992。200 μg/L标准溶液重复进样8 次, 柠檬酸峰面积的相对标准偏差即精密度为0.77%。运用该方法测定市售5 种不同品牌葡萄酒样品中柠檬酸的含量, 并对样品加标回收, 得回收率大于95%。结论 该方法可以满足葡萄酒中柠檬酸定量分析的要求, 且有效改善了分析的灵敏度和准确性。

英文摘要:

      Objective To establish a rapid method for determination of citric acid in wine samples by ion chromatography-electrospray ionization tandem mass spectrometry (IC/ESI-MS) in the negative ESI and se-lected ion monitor (SIM) mode. Methods Citric acid was separated by high capacity and hydroxide selective column IonPac AS20 with KOH eluent generated from EGC. Peak area of citrate ion (m/z=191) was monitored for quantifying. Results The limit of detection was 17.6 μg/L for citric acid. A linear calibration was obtained over the range from 50 to 1000 μg/L with a correlation coefficient of 0.9992. The relative standard deviation for 8 injections of standard solution (200 μg/L) was 0.77%. This method was applied to detect the citric acid in different kinds of wine samples which were purchased in market, and the rates of recovery were higher than 95%. Conclusion The method could meet the requirements of quantitative analysis of citric acid in wine samples, and also could improve the sensitivity and accuracy of the analysis.