Improved LC−MS Method for the Determination of Fatty Acids in Red Blood Cells by LC−Orbitrap MS
作者:Xingnan Li、Adrian A. Franke
DOI:10.1021/ac103093w
日期:2011.4.15
We report a new method for fast and sensitive analyses of biologically relevant fatty acids (FAs) in red blood cells (RBC) by liquid chromatography mass spectrometry (LC−MS). A new chemical derivatization approach was developed forming picolylamides from FAs in a quantitative reaction. Fourteen derivatized FA standards, including saturated and unsaturated FAs from C14 to C22, were efficiently separated within 15 min. In addition, the use of a recently introduced benchtop orbitrap mass spectrometer under positive electrospray ionization (ESI) full scan mode showed a 2−10-fold improvement in sensitivity compared with a conventional tandem MS method, with a limit of detection in the low femtomole range for saturated and unsaturated FAs. The developed method was applied to determine FA concentrations in RBC with intra- and interday coefficients of variation below 10%.
我们报告了一种通过液相色谱质谱联用(LC−MS)快速且灵敏分析红细胞(RBC)中生物学相关的脂肪酸(FAs)的新方法。该方法开发了一种形成吡啶甲酰胺的新化学衍生化途径,通过定量反应从FAs中生成。包括从C14到C22的饱和及不饱和FAs在内的14种衍生化FA标准品,在15分钟内得以高效分离。此外,采用最近推出的台式轨道阱质谱仪在正离子电喷雾电离(ESI)全扫描模式下进行检测,相较于传统串联MS方法,灵敏度提高了2至10倍,对饱和及不饱和FAs的检测限达到了低飞摩尔水平。所开发的方法被应用于测定RBC中的FA浓度,其日内和日间变异系数均低于10%。