HPLC法测定婴幼儿配方乳粉中羧甲基赖氨酸

Determination of Carboxymethyl Lysine in Infant Formula Milk Powder

乳由于热损伤而发生美拉德反应,产生羧甲基赖氨酸(CML)。研究显示,CML与糖尿病、动脉粥样硬化、人体细胞老化等均呈正相关。本文建立了HPLC方法对婴幼儿乳粉中羧甲基赖氨酸的测定方法。样品经预处理,采用高效液相色谱仪(HPLC)进行测定,色谱柱为C18柱,柱温为35℃,流动相为甲醇和醋酸钠缓冲液(p H 6.50,0.048 mol/L)(96∶4,体积比),流速为0.8 m L/min,荧光检测器,激发波长340 nm,发射波长455 nm,外标法定量。结果显示,CML在0.2μg/m L^35.0μg/m L范围内呈良好线性关系,相关系数(r)为0.999 1。最低检出浓度为0.16μg/m L。选择市售2种品牌奶粉进行加标回收试验,回收率分别为92%和107%。

Maillard reaction produced carboxymethyl lysine（CML） when milk had been heat injury. Research showed that positive correlation between CML and diabetes mellitus, atherosclerosis and aging cells of people.This paper established high performance liquid chromatography（HPLC） method for determination of carboxymethyl lysine in infant formula products. After pre-treating the sample was quantified with external standard method used C18 chromatographic column with the temperature 35 ℃ and methanol-Sodium acetate buffer（p H 6.50,0.048 mol/L）（96 ∶ 4,volume ratio）as mobile phase at a flow rate of 0.8 m L/min by FLD detector at 340 nm and 455 nm as excitation and emission wavelength. The result showed that CML had a good linearity in the range of 0.2 μg/m L-35.0 μg/m L, and the correlation coefficient was 0.999 1. The limit concentration of detection was 0.16 μg/m L. The recovery rate were 92 % and 107 % in standard recovery test which choosed two brands of milk powder.