GC-MS同时测定多不饱和脂肪酸微胶囊中氯丙醇酯和缩水甘油酯的含量

Simultaneous determination of chloropropanol ester and glycidyl ester in microencapsulated polyunsaturated fatty acids by gas chromatography-mass spectrometer

建立了检测多不饱和脂肪酸微胶囊中氯丙醇酯和缩水甘油酯的同位素稀释气相色谱-质谱(GCMS)法。首先使用石油醚、乙醇等对微胶囊中的油脂进行多次的萃取,萃取所得的油脂经四氢呋喃,酸性溴化钠、正庚烷脱脂净化以及苯基硼酸的衍生化后,再使用正庚烷萃取衍生物两次,萃取液经氮气吹干,复溶、再过膜进样,最后使用内标法定量,文中所测氯丙醇酯和缩水甘油酯的含量,分别以氯丙醇和缩水甘油计。结果表明:3-MCPD标曲的相关系数为0.999,检出限为0.05mg/kg,线性范围:0.11~16.5μg/m L;2-MCPD标曲的相关系数为0.999,检出限为0.05mg/kg,线性范围:0.110~16.995μg/m L;缩水甘油标曲的相关系数为0.999,检出限0.03mg/kg,线性范围:0.055~3.3μg/m L。样品的加标回收率均在93.5%~115.2%,相对标准偏差(RSD)在3.0%~5.7%之间(n=6),说明该方法准确可靠,可用于多不饱和脂肪酸微胶囊中氯丙醇酯和缩水甘油酯的分析测定。

A method of determining chloropropanols ester and glycidol ester content in microencapsulated polyunsaturated fatty acids by isotope dilution- gas chromatography- mass spectrometry（GC- MS） was established.Oil in microencapsulated powder was extracted several times with petroleum ether and ethanol.The sample was then defatted and purified by tetrahydrofuran,acidic sodium bromide and n- heptane,and derivatized with phenylboronic acid.After extracted by N- heptanen twice,the derivatives were dried with nitrogen and redissloved.GC- MS with internal standard method was used for quantitative analysis.The results showed that the coefficient correlations for 3-MCPD,2-MCPD,GLy were 0.999,0.999,0.999;the limits of detection（LOQ） for 3-MCPD,2-MCPD,GLy were 0.05mg/kg、0.05mg/kg、0.03mg/kg,respectively.The method showed good linearity between 0.11 ～ 16.5μg/mL for 3- MCPD,0.110～16.995 μg/mL for 2- MCPD,0.055 ～3.3 μg/mL for Gly.The recoveries were all between 93.5%～ 115.2%;RSD were between 3.0%～5.7%（n=6）.This GC- MS method was accurate and reliable for the determination of chloropropanols in microencapsulated polyunsaturated fatty acids.