离子色谱法测定蔬菜的草酸含量

本文叙述一种使用离子色谱技术测定蔬菜中草酸含量的新方法。该法只需简单的样品制备:将样品捣成匀浆,用盐酸酸化,在沸水中煮一小时,过滤,用去离子水按需要稀释,再通过0.2μm孔径的微孔滤膜,就能直接注入离子色谱仪分析。每分析一个样品仅需20分钟。最低检出限为0.1ppm(1.1μmol/L),线性范围1～1000ppm,批内和批间变异系数分别为2.7％和3.2％,平均回收率99.6％。本方法简便、快速、准确,可用于蔬菜中草酸含量的测定。

ION-CHROMATOGRAPHIC DETERMINATION OF OXALATE IN VEGETABLE

A new method for determination of oxalate in vegetable by means of ion-chromatographic technique is presented. The technique only required simple sample preparation. The sample was ground into puree and acidified with HC1, bathing in boling water for one hour, and filtered. The filtrate was diluted with de-ionized distilled water as required and re-filtered through a 0.2 um pore size millipore filter. A digest of the sample was injected into an ion-chromatograph for determination. It only required about 20 min to analyse a sample.The minimum detection limit of oxalate was 0.1 ppm (1.1 umol/L). The calibration linear curve was in the range from 1 to 1000 ppm. The coefficient of variation for intraassay was 2.7%, for interassay was 3.2%. The average recovery was 99.6%. This method is simple, rapid and accurate for analysing oxalate in vegetable.