Eluent Generator Reagent Free Ion Chromatography with Electrospray Ionization Mass Spectrometry for Simultaneous Analysis of Organic Acids in Juices and Beverages

Abstract

A new analytical method is proposed for simultaneous determination of twenty organic acids in juices and beverages by eluent generator reagent free ion chromatography with electrospray ionization mass spectrometry (ESI–MS) in the negative selected ion monitoring mode (SIM). Twenty organic acids showed good linear relationship in the ranges of 0.5 ∼ 20.0 mg/L. The correlation coefficients were more than 0.998, the detection limits were between 0.05 ∼ 0.5 mg/L, and the average recoveries were between 88.0% ∼ 106.0%. The relative standard deviations (RSDs) were less than 7.6%. The method has been applied to juice and beverage samples with satisfactory results.

Keywords:

• Electrospray ionization mass spectrometry
• Organic acid
• Reagent free ion chromatography

This work was supported by a grant from the Medicine Science Foundation of Ningbo, Zhejiang Province, China (2006048) and by the National Natural Science Foundation of China (No. 20775070) by Zhejiang Provincial Natural Science Foundation of China (No. R4080124), and the Zhejiang Qianjiang Project of Science and Technology for the assistance of competent people (2008R10028).

Notes

^a The concentration was determined by the developed IC-ESI-MS method.

^a Values in the bracket were determined by IC-CD method.

^a The simulated beverage and grape wine were prepared by the real world sample with additional of some organic acids. The concentration values were determined by dilution 1:25.

^b Determined five replicates each day within continuous three days.

^c The values were determined for dilution 1:100.

^a n.d.: not detected.