摘要
通过直接采集碎片离子的高精度质量数(分辨率> 70 000,m/z 200),利用元素模拟得到碎片离子的元素组成,进而探究氯丙醇双酯的质谱裂解规律。结果表明:氯丙醇双酯存在以脂肪酸或酮基形式的中性丢失,形成一系列的碎裂片段:[RCH_(2)COOH+H]^(+),[RCH==CO+H]^(+)和[*g-H_(2)O]^(+)等,这些离子可用于鉴定脂肪酸链组成。在高碰撞能下,脂肪酸链的骨架结构形成一系列Δ=14 u的碎片离子,质荷比分布为100~210 u。值得注意的是,氯丙醇双酯在一定的碰撞能量范围内,sn-1/3位酰基链形成的碎裂片段总大于sn-2位对应的离子碎片,该结论可实现对氯丙醇双酯酰基链位置的准确鉴定。基于上述裂解规律,在植物油中共鉴定出9种3-氯丙醇双酯,含量为(7.12±0.54)~(24.24±2.01) mg/kg。
The elemental composition of fragment ions was obtained by directly collecting the high precision mass number of fragment ions(resolution > 70 000,m/z 200),and then the cracking laws of chloropropanol diesters were investigated by elemental simulation.Results showed that chloropropanol diesters have neutral ions in the form of fatty acids or ketoacids,forming a series of fragmentation fragments,including [RCH_(2)COOH + H]^(+),[RCH= =CO + H]^(+)and [*g-H_(2)O]^(+),etc,which could be used to identify the composition of fatty acyl chain. Under high collision energy,the fatty acid chain skeleton structure could also form a series of Δ = 14 u fragment ions,with a mass-charge ratio distributed between 100 u and 210 u.Notably,when chlorpropanol diesters is under a certain range of collision energy,the fragmentation fragments formed by the acyl chain at sn-1/3 are always greater than the corresponding ionic fragments at sn-2,which could realize the identification on position from the diester acyl.Nine 3-chloropropanol diesters in vegetable oil were identified,with total content from(7. 12 ± 0. 54) mg/kg to(24. 24 ± 2. 01) mg/kg.
作者
周洁
孙骥
余晓玲
于子丰
李双
ZHOU Jie;SUN Ji;YU Xiao-ling;YU Zi-feng;LI Shuang(Ningbo Zhongsheng Product Testing Company,Ningbo 315040,China;Ningbo Customs Technology Center,Ningbo 315040,China)
出处
《分析测试学报》
CAS
CSCD
北大核心
2023年第1期11-20,共10页
Journal of Instrumental Analysis
