离子色谱法测定黄原胶中丙酮酸含量

Measurement of Pyroracemic Acid in Xanthan Gum with Ion Chromatography

采用离子色谱仪,建立了一种快捷测定黄原胶中丙酮酸含量的方法.以20 mmol/L KOH溶液为淋洗液,AS19分离柱（250 mm×4 mm）分离,电导检测器检测,柱温和检测器温度为30℃,进样量为10 μL,流速为1.0 mL/min,峰面积定量.丙酮酸的检出限为0.01 mg/L,在2～15 mg/L范围内具有良好的线性关系（R2=0.999 6）,加标回收率均在96％以上,相对标准偏差（RSD）为1.0％～1.2％.经实验表明,此方法简单、快速,可便捷地应用于黄原胶样品中丙酮酸含量的测定.

A quick measurement of pyroracemic acid in xanthan gum was established using ion chromatography. The specification of the ion chromatography is as follows: 20 mmol/L KOH solution as eluent, AS19 separation column(250 mm × 4 mm), electric conductivity detector, temperature of the separation column and detector is 30 ℃, quantity of sample fed is 10μL, flow rate is 1.0 mL/min, and peak area is used for calculation. The detectability of pyroracemic acid is 0.01 mg/L, and good linearity(R2=0.9996) was obtained in a range of 2-15 mg/L. The spiked recoveries were all above 96%, and relative standard deviation(RSD) 1.0%-1.2%. Laboratory test shows that this is a simple, quick method for the determination of pyroracemic acid in xanthan gum.