气相色谱-质谱法测定血浆中31种游离脂肪酸含量

Determination of 31 Free Fatty Acids in Plasma by Gas Chromatography-Mass Spectrometry

建立了气相色谱-质谱(GC-MS)检测血浆中31种游离脂肪酸(FFAs)含量的分析方法。通过比较和优化FFAs提取富集及衍生化方法,确定以氯仿∶甲醇(体积比1∶2)为提取溶剂,乙酰氯法为衍生化方法。结果表明,31种FFAs在各自的浓度范围内线性良好,相关系数(r)不低于0.9990;方法的检出限(LOD,S/N≥3)和定量下限(LOQ,S/N≥10)分别为0.010~0.050μg/mL和0.034~0.167μg/mL。以C13∶0和C23∶0为目标物质,进行方法学验证,血浆质控样的回收率为86.3%~115%,相对标准偏差(RSD,n=6)不大于9.6%,日内RSD(n=6)不高于6.3%,日间RSD(n=3)不高于7.8%。将方法应用于49份孕妇血浆中FFAs含量的测定,测得21~31种FFAs,其中C16∶0(棕榈酸)、C18∶2n6c(亚油酸)、C18∶1n9c(油酸)和C18∶0(硬脂酸)等为孕妇血浆的主要FFAs。该方法能检出更多的FFAs种类,且所需样本量少,具有更低的LOD和LOQ,定性定量准确,可用于血浆中FFAs的分析。

A gas chromatography-mass spectrometric(GC-MS) method was developed for the simultaneous determination of 31 free fatty acids(FFAs) in plasma.By comparing and optimizing the extraction and derivatization of FFAs from plasma,a solution of chloroform :methanol(1 ∶2,by volume) was selected to extract FFAs,and acetyl chloride was used for the FFAs derivatization before GC-MS detection.Results indicated that there were good linear relationships for 31 FFAs in their respective concentration ranges,with correlation coefficients(r) not less than 0.999 0.The limits of detection(LOD) and the limits of quantitation(LOQ) were in the ranges of 0.010-0.050 μg/mL and 0.034-0.167 μg/mL,respectively.When C13 ∶0 and C23 ∶0 were used as target compounds to valify the method,the average recoveries for plasma quality ranged from 86.3%-115%,with the intra-day RSDs(n=6) not more than 6.3% and the inter-day RSDs(n=3) not more than 7.8%.The developed method was applied to detect the FFAs in the plasma samples of 49 pregnant women.21-31 FFAs were detected in the plasma,among which C16 ∶0(palmitic acid),C18 ∶2 n6 c(linoleic acid),C18 ∶1 n9 c(oleic acid) and C18 ∶0(stearic acid) were the main fatty acids.With more fatty acids detected,smaller sample volume required,lower LOD and LOQ as well as better accuracy of qualitation and quantitation,the proposed method is more suitable for the analysis of FFAs spectrum in plasma.