基于超高效液相色谱-串联质谱同时测定婴幼儿配方乳粉中2'-岩藻糖基乳糖和乳糖-N-新四糖OA北大核心CSTPCD

A method was established to simultaneously determine 2'-fucosyllactose(2'-FL)and lactose-N-neotetraose(LNnT)in in-fant milk powder by ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The sample was extracted by water,precipitated protein,and purified through a needle-type water system filtration membrane.Then the sample solution was separated using an amide column by gradient elution,within acetonitrile and 10 mmol/L ammonium formate aqueous solution(containing 0.1％for-mic acid,V/V).The selective reaction monitoring mode was used to measure and quantify by external standards.In addition,it also evalu-ated the solvent effect and matrix effect by dilution method and extraction addition respectively.Results showed that the addition ion peaks[M+NH4+]and[M+H+]of 2'-FL and LNnT in the positive ion mode were better than others.After the gradient conditions and flow rate optimization,both 2'-FL and LNnT could be eluted within 8 min.However,it was found that 2'-FL and LNnT had serious solvent effects,while,in the elimination test,the effect could be eliminated using 50％acetonitrile ammonium formate aqueous solution as the di-luted solvent,within 20 times dilution.The linear ranges of 2'-FL and LNnT were 5.0-150.0 ng/mL and 2.5-75.0 ng/mL,respective-ly.And there was no matrix effect in either 2'-FL or LNnT.The method verification showed that the precision and accuracy parameters of 2'-FL and LNnT met the requirements of the national standard,and this method was suitable for the simultaneous determination of 2'-FL and LNnT in infant formula.