血清中游离脂肪酸的液相色谱荧光测定及质谱鉴定

利用新型荧光试剂1,2 苯并 3,4 二氢咔唑 9 乙基对甲苯磺酸酯(BDETS)对19种游离脂肪酸(FFAs)进行柱前衍生,在EclipseXDB C8反相色谱柱上,采用梯度洗脱优化分离.90℃下在DMF溶剂中以K2CO3作催化剂,衍生反应30min获得稳定的荧光产物.激发和发射波长分别为λex=333nm,λem=390nm,采用大气压化学电离源(APCI)正离子模式进行柱后在线质谱定性.多数脂肪酸的线性回归系数大于0.9989,检测限为24.80～80.37fmol.实现了人体血清中长链脂肪酸的定性及相应含量测定.

Determination of Free Fatty Acids in Serum by Liquid Chromatography Mass Spectrum with Fluorescence Detector

On a reversed-phase Eclipse XDB-C_8 column, 19 free fatty acids (FFA) derivatized using 1,2-benzo-3,4-dihydrocarbazole -9-ethyl-toluene-4-sulfonate (BDETS) as pre-column derivatization reagent were separated in conjunction with a gradient elution. Optimum derivatization, giving the corresponding stable fluorescent derivatives, were done by reacting of fatty acids with BDETS at 90℃ for 30 min in the presence of K_2CO_3 as catalyst in DMF solvent. The fluorescence excitation and emission wavelengths were set at 333 nm λ_ex and 390 nm λ_em, respectively. The identification of long-chain FFA derivatives was obtained on the basis of APCI detection at positive mode. Correlation coefficients for FFA derivatives are >0.998 9, and detection limits at signal-to-noise of 3:1 are 24.80～80.37 fmol for the labeled FFAs. The established method is sensitive and reproducible for the determination of FFAs in extracted serum with satisfactory results.