特殊医学用途婴儿配方食品中乳铁蛋白的检测

Detection of Lactoferrin in Formulas for Special Medical Purposes Intended for Infants

建立特殊医学用途婴儿配方食品中乳铁蛋白的高效液相色谱(high performance liquid chromatography,HPLC)检测方法。试样中的乳铁蛋白经磷酸盐缓冲液提取,肝素亲和柱净化后,用反相-HPLC分离,以0.1%三氟乙酸和乙腈作为流动相进行梯度洗脱,HPLC仪紫外检测器检测,外标法定量。结果表明:在乳铁蛋白质量浓度50~500μg/mL范围内,检测结果呈现良好线性关系;该方法的检出限为5 mg/100 g,定量限为15 mg/100 g,平均回收率为93.9%;同一质量浓度乳铁蛋白标准溶液的测定相对标准偏差(relative standard deviation,RSD)为0.12%,稳定性实验中平行实验检测结果的RSD为0.96%;能力验证结果表明可靠性好。此方法方便、快捷、准确、可靠、重复性好,能够有效检测特殊医学用途婴儿配方食品中乳铁蛋白的含量。

In this study,a high performance liquid chromatography(HPLC)method was developed for the determination of lactoferrin in formulas for special medical purposes intended for infants.Lactoferrin from samples was extracted with phosphate buffer.After being purified on a heparin affinity column,the analyte was separated by reversed-phase HPLC using gradient elution with 0.1%trifluoroacetic acid and acetonitrile mixture as the mobile phase,detected by a UV detector and quantitated by the external standard method.Results showed that good linearity was observed for lactoferrin in the concentration range of 50–500μg/mL.The detection limit of the method was 5 mg/100 g,and the quantitation limit was 15 mg/100 g.The average recovery was 93.9%.The precision expressed as relative standard deviation(RSD)was 0.12%,and the stability RSD was 0.96%.Proficiency testing confirmed the reliability of the method.This method was convenient,fast,accurate,reliable and reproducible,and could effectively detect lactoferrin in formulas for special medical purposes intended for infants.