关键词: 离子色谱, 脉冲安培检测, 梯度洗脱, 婴幼儿配方乳粉, 多种糖类

Abstract: The purpose of this study is to establish a simple, rapid and effective method for the simultaneous analysis of various saccharides (glucose, sucrose, lactose, galactooligotrisaccharide, kestose, galactooligopentasaccharide, nystose and 1F-fructofuranosyl nystose) in infant formula by high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). The effect of chromatographic columns, column temperature, detector waveforms, eluent concentration and flow rate on the separation of the 8 saccharides was evaluated. The analysis was performed on a CarboPac PA20 analytical column (3 mm × 150 mm) coupled with a guard column (3 mm × 30 mm) at a 0.30 mL/min flow rate. Column temperature was set as 30 ℃. Efficient separation was achieved using gradient elution. Under the optimal conditions, the detection limit was 3.0–12.0 μg/L for all analytes. The precision, expressed as relative standard deviation (RSD), was less than 3%. The recoveries of the 8 saccharides in spiked soymilk were 78.0%–96.8%, indicating the feasibility of this method.

Key words: ion chromatography, pulsed amperometric detection, gradient elution, infant formula, a variety of sugars