Chen Q C, Wang J
China Import & Export Commodity Inspection Technology Institute, Beijing.
J Chromatogr A. 2001 Dec 7;937(1-2):57-64. doi: 10.1016/s0021-9673(01)01306-1.
A novel ion chromatographic method was proposed for the simultaneous determination of artificial sweeteners (sodium saccharin, aspartame, acesulfame-K), preservatives (benzoic acid, sorbic acid), caffeine, theobromine and theophylline. The separation was performed on an anion-exchange analytical column operated at 40 degrees C within 45 min by an isocratic elution with 5 mM aqueous NaH2PO4 (pH 8.20) solution containing 4% (v/v) acetonitrile as eluent, and the determination by wavelength-switching ultraviolet absorbance detection. The detection limits (signal-to-noise ratio 3:1) for all analytes were below the sub-microg/ml level. Under the experimental conditions, several organic acids, including citric acid, malic acid, tartaric acid and ascorbic acid, did not interfere with the determination. The method has been successfully applied to the analysis of various food and pharmaceutical preparations, and the average recoveries for real samples ranged from 85 to 104%. The levels of all analytes determined by this method were in good agreement with those obtained by the high-performance liquid chromatographic procedure. The results also indicated that ion chromatography would be possibly a beneficial alternative to conventional high-performance liquid chromatography for the separation and determination of these compounds.
提出了一种新型离子色谱法，用于同时测定人工甜味剂（糖精钠、阿斯巴甜、安赛蜜-K）、防腐剂（苯甲酸、山梨酸）、咖啡因、可可碱和茶碱。分离在阴离子交换分析柱上进行，柱温40℃，采用含4%（v/v）乙腈的5 mM NaH2PO4水溶液（pH 8.20）等度洗脱，45分钟内完成，采用波长切换紫外吸收检测法进行测定。所有分析物的检测限（信噪比3:1）均低于亚微克/毫升水平。在实验条件下，包括柠檬酸、苹果酸-、酒石酸和抗坏血酸在内的几种有机酸不干扰测定。该方法已成功应用于各种食品和药物制剂的分析，实际样品的平均回收率为85%至104%。用该方法测定的所有分析物的含量与高效液相色谱法测定的结果高度一致。结果还表明，离子色谱法可能是传统高效液相色谱法分离和测定这些化合物的有益替代方法。
