关键词: 特殊医学用途配方食品, 天冬酰胺, 谷氨酰胺, 酶解, 柱后衍生阳离子交换色谱法

Abstract: [Objective] To establish a post-column derivatization cation exchange chromatography method for determining the contents of asparagine and glutamine in foods for special medical purposes.[Method] The samples were enzymatically hydrolyzed with Streptomyces griseus protease,and the supernatant was collected after centrifugation.It was then separated on a cation exchange chromatography column,derivatized with ninhydrin.The absorbance was detected at 570 nm,and the quantitative analysis was performed using the external standard method.[Result] Asparagine and glutamine exhibited good linearity in the range of 10-250 μmol/L（R²>0.9999）.The limits of quantification was 1.4 μmol/L and 1.1 μmol/L,respectively,the recovery rate was 96.5%-101.1%,and the RSD was 1.0%-2.2%.[Conclusion] This method demonstrated good repeatability and high accuracy,overcoming the drawbacks of complicated operations and poor repeatability associated with pre-column derivatization.It can serve as a complementary approach to the national standard methods,providing technical support for quality control of foods for special medical purposes and government supervision.

Key words: food for special medical purposes（FSMP）, asparagine, glutamine, enzymatic hydrolysis, post-column derivatization cation exchange chromatography