鲜乳及乳粉中L-羟脯氨酸的柱前衍生高效液相色谱测定法

目的建立柱前衍生反相高效液相色谱测定鲜乳及乳粉中L-羟脯氨酸方法。方法样品经酸水解,采用异硫氰酸苯酯(PITC)与水解液中的L-羟脯氨酸衍生,以C18柱分离,紫外检测器254 nm波长下检测。结果在2～10 mg/L范围内,L-羟脯氨酸质量浓度与峰面积具有良好的线性关系,样品加标平均回收率为95.0%～100.3%,方法精密度为0.4%～4.0%。鲜乳的检出限为2.0 mg/kg,乳粉的检出限为14 mg/kg。结论该方法易于操作、稳定、准确,适用于鲜乳及乳粉中L-羟脯氨酸检测。

Determination of L-hydroxyproline in milk and milk powder by pre-column derivatization HPLC

[Objective]To establish a method to determine L-hydroxyproline in milk and milk powder by pre-column derivatization HPLC.[Methods]The sample was treated by acid hydrolysis,L-hydroxyproline in hydrolysis liquid were derived with PITC,separated by C18 column,the content of L-hydroxyproline was determined with UV detector at 254 nm.[Results]There was a good linear relationship between the peak and the concentration of the L-hydroxyproline in the range of 2-10 mg/L,The recoveries were 95.0-100.3%,and the RSD was 0.4%-4.0%.the detection limit of milk was 2.0 mg/kg,the detection limit of milk powder was 14 mg/kg.[Conclusion]The method is simple,steady and accurate,and it is suitable for determination of L-hydroxyproline in the milk and milk powder.