离子转换色谱-紫外检测法测定啤酒中的无机阴离子和有机酸

建立了离子转换色谱与紫外检测器联用检测啤酒中无机阴离子与有机酸的新方法。在传统的离子色谱基础上引入两根离子转换柱，无机阴离子与有机酸经过两步转换，定量转换成有相同紫外响应的碘酸盐，然后用紫外检测器代替电导检测器进行定量分析。在Dionex AS11-HC阴离子色谱柱上，采用KOH梯度淋洗方式实现了12种无机阴离子与有机酸的分离。结果表明，12种无机阴离子和有机酸检出限（S/N=3）与定量限（S/N=10）分别为6.168~29.01 μg/L与20.56~66.30 μg/L；线性关系良好（r在0.9994以上），回收率为89.0%~117.0%，RSD均小于1.0%，该方法与传统的电导检测器检测结果相当。该方法简单快捷，只需采用少数标准曲线，就可以实现啤酒中无机离子与有机酸的定量测定。

Determination of inorganic anions and organic acids in beer by replacement-ion chromatography with ultraviolet detection

A new method for determination of inorganic anions and organic acids in beer was developed by replacement-ion chromatography-ultraviolet detection. Two ion replacement columns were introduced on the basis of the traditional ion chromatography. Inorganic anions and organic acids were converted into iodate salts with the same ultraviolet response, and then detected sensitively by ultraviolet detector instead of conductivity detector. The separation of the inorganic anions and organic acids was achieved on a Dionex AS11-HC anion chromatographic column with KOH as gradient eluent. The results showed that the limits of detection (S/N=3) and the limits of quantification (S/N=10) were 6.168-29.01 μg/L and 20.56-66.30 μg/L respectively; the linear relationship is good with correlation coefficients (r) greater than 0.9994. The average recoveries were between 89.0% and 117.0%, and relative standard deviations (RSDs) were all less than 1.0%, the detection results are almost the same with the results of traditional conductance. The method is simple, rapid and can realize the determination of inorganic ions and organic acids in beer using use a few standard curves.