白酒中甜蜜素的无衍生离子色谱法检测

Determination of Sodium Cyclamate in Distillate Spirits by Non-derivatized on Chromatography

建立了免化学试剂离子色谱一抑制电导检测白酒中甜蜜素的方法。选用DionexIonpacAS17（250mm×4min）分离柱，优化了电解水在线产生KOH淋洗液的梯度淋洗程序，样品无需衍生化，稀释后过0．22μm滤膜及OnGuardIIRP离子色谱前处理小柱后直接进样检测，外标法定量。在0．05—20．0mg／L范围内，甜蜜素的质量浓度与色谱峰面积呈良好的线性关系（r2=0．9992），检出限为0．072mg／L；峰面积和峰高的相对标准偏差（n=10）分别为1．6％、2．0％；加标回收率为85％一103％。该方法简便易行、误差因素少，无干扰、选择性好、灵敏度高、分析结果准确，适用于白酒中甜蜜素的检测。

A method based on the electrochemical behavior of cyclamate anion in alkaline solution was developed for the determination of sodium cyclamate in distilled spirits by non-derivatized ion chromatography with suppressed conductivity detection. The diluted sample was pretreated by passing through 0. 22 μm filter membrane and OnGuard Ⅱ RP chromatographic column, respectively, prior to sample detection for the removal of interferents. A low-capacity and strong hydrophilic anion exchange column, Dionex Ionpac ASI7 （250 mm × 4 mm）was used with gradient elution. The KOH eluant was produced on-line using electrolyzed water. Peak area was used for quantitative measure- ment with external standard calibration. Results showed that the mass concentration of sodium cycla- mate had a linear relationship with the chromatographic peak area in the range of 0. 05 -20.0 mg/L. The detection limit was 0. 072 mg/L and the relative standard deviations（n = 10） for peak area and peak height measurements were 1.6% and 2. 0% , respectively. The spiked recoveries ranged from 85% to 103%. Analytical results showed that the proposed method was simple, selective, sensitive and easy to operate, and was suitable for the determination of sodium cyclamate in distilled spirits.