Chen Qin, Li Ying, Dong Lezhen, Shi Ranran, Wu Zhen, Liu Lianliang, Zhang Jingshun, Wu Zufang, Pan Daodong
Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315832, Zhejiang Province, PR China.
Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315832, Zhejiang Province, PR China.
Food Chem. 2022 Aug 15;385:132697. doi: 10.1016/j.foodchem.2022.132697. Epub 2022 Mar 14.
This study developed a sensitive and easy method to directly analyze N-(carboxymethyl)lysine (CML) by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Acetonitrile and water were used as the binary mobile phase without ion pair reagents, while BEH Amide column was applied to detect CML. The target substance without derivatization could be well retained and separated after the pretreatment conditions were optimized. Oasis MCX solid phase extraction (SPE) cartridge showed the best recovery rate of CML 96.7 % and purification ability among the tested SPE cartridges. There was no obvious difference in pretreatment abilities with or without protein precipitation on the CML quantitative analysis. The recovery rates 97-98 % for CML were achieved by UPLC-MS/MS, as well as the detection limit and quantification limit were 0.05 mg/kg and 0.15 mg/kg sample, respectively. This method was suitable for quantifying CML content with high recovery rate and low detection and quantification limit in sterilized milk.
本研究开发了一种灵敏且简便的方法，通过超高效液相色谱串联质谱法（UPLC-MS/MS）直接分析N-(羧甲基)赖氨酸（CML）。以乙腈和水作为二元流动相，无需离子对试剂，同时使用BEH酰胺柱检测CML。在优化预处理条件后，未衍生化的目标物质能够得到良好的保留和分离。在测试的固相萃取（SPE）小柱中，Oasis MCX SPE小柱对CML的回收率最高，为96.7%，且具有最佳的净化能力。在CML定量分析中，有无蛋白质沉淀的预处理能力无明显差异。通过UPLC-MS/MS实现了CML 97-98%的回收率，其检测限和定量限分别为0.05 mg/kg样品和0.15 mg/kg样品。该方法适用于定量无菌牛奶中CML的含量，回收率高，检测限和定量限低。
