柱前衍生-高效液相色谱法测定乳及乳制品中5种乳糖衍生物

Determination of 5 kinds of lactose derivatives in milk and dairy products by pre-column derivatization-high performance liquid chromatography

中文关键词:  乳与乳制品  高效液相色谱  乳糖衍生物  3’-半乳糖基乳糖  4’-半乳糖基乳糖  6’-半乳糖基乳糖  3’-唾液酸乳糖  6’-唾液酸乳糖  

英文关键词:milk and dairy products  high performance liquid chromatography  lactose derivatives

中文摘要:

      目的 建立柱前衍生-高效液相色谱法测定乳及乳制品中5种乳糖衍生物(3’-半乳糖基乳糖、4’-半乳糖基乳糖、6’-半乳糖基乳糖、3’-唾液酸乳糖、6’-唾液酸乳糖)含量的定量分析方法。方法 乳及乳制品经沉淀蛋白, 于55 ℃下5种乳糖衍生物与2-氨基苯甲酰胺反应120 min, 标记上荧光基团, 经高效液相色谱酰胺柱分离, 外标法定量5种乳糖衍生物的含量。结果 5种乳糖衍生物在0.025~5.000 mg/L质量浓度范围内线性关系良好, 相关系数(r)均大于0.999; 5种乳糖衍生物的检出限和定量限在3.5~7.5 mg/kg和12.0~25.0 mg/kg之间; 5种乳糖衍生物的的回收率在90.8%~103.3%, 检测结果的相对偏差在2.8%~5.3% (n=3)。结论 本方法的精密度和回收率良好, 灵敏度较好, 可用于乳与乳制品中5种乳糖衍生物含量的测定。

英文摘要:

      Objective To establish a quantitative analysis method for determining the content of 5 kinds of lactose derivatives (3’-galactosyllactose, 4’-galactosyllactose, 6’-galactosyllactose, 3’-sialyllactose, 6’-sialyllactose) in milk and dairy products by pre-column derivatization-high performance liquid chromatography. Methods The proteins in milk and dairy products were precipitated. The 5 kinds of lactose derivatives were reacted with 2-aminobenzamide at 55 ℃ for 120 min to label the fluorescent groups. The 5 kinds of lactose derivatives were separated by high performance liquid chromatography with an amide column and quantified by external standard method. Results The 5 kinds of lactose derivatives exhibited good linear relationships within the concentration range of 0.025–5.000 mg/L, with correlation coefficients (r) all exceeding 0.999. The limits of detection and quantification for the 5 kinds of lactose derivatives ranged from 3.5 to 7.5 mg/kg and 12.0 to 25.0 mg/kg, respectively. The recovery rates for the 5 kinds of lactose derivatives were between 90.8% and 103.3%, with relative deviations in detection results ranging from 2.8% to 5.3% (n=3). Conclusion This method demonstrates good precision, recovery rate, and sensitivity, making it suitable for determining the content of 5 kinds of lactose derivatives in milk and dairy products.