Direct Injection Method for Quantitation of Endogenous Leukotriene E4 in Human Urine by Liquid Chromatography/Electrospray Ionization Tandem Mass Spectrometry with a Column-switching Technique

Abstract

A new analytical method employing liquid chromatography/tandem mass spectrometry (LC/MS/MS) with a columnswitching system was developed for quantitative determination of leukotriene E4 (LTE4) in human urine. A columnswitching system using a trapping column, which concentrates the analyte and removes salts and other water-soluble contaminants, allowed direct injection of human urine. Because simultaneously eluted endogenous contaminants suppressed the ionization efficiency of LTE4, good liquid chromatographic separation was very important for establishing this method, notwithstanding the high selectivity of MS/MS. The calibration curve was linear over the range from 10 to 3000 pg/mL, and the method showed good accuracy and precision. This method should therefore be very useful for determination of LTE4 amounts in human urine in studies on leukotriene metabolism and the efficacy of antileukotriene drugs.

Advances in analytical mass spectrometry to improve screening for inherited metabolic diseases

“…In some peroxisomal disorders, in particular in peroxisome biogenesis defects, the ability to chain-shorten C(27) bile acid intermediates into C(24) bile acids is impaired resulting in elevated plasma concentrations of free and taurine-conjugated C (27) bile acids such as di-and trihydroxycholestanoic acid diastereoisomers as recently demonstrated by LC-MS/MS [11]. This method also allows the separation of the isomeric forms.…”

“…Recently, the first inborn error of leukotriene synthesis, LTC 4 -synthesis deficiency, was identified in association with a fatal developmental syndrome and the absence of leukotrienes in plasma, urine, and cerebrospinal fluid [40]. The development of a new LC-MS/MS method for the analysis of LTE 4 might be the starting point for a more widespread urinary screening in patients at risk [27].…”

A simple and robust UPLC-SRM/MS method to quantify urinary eicosanoids

“…F ) LTE 4 , a metabolite of LTD 4 formed from LTC 4 ; leukotriene synthesis is regulated by 5-lipoxygenase ( 10,21 ). LTE 4 is used as biomarker to predict asthma and is believed to refl ect the whole body LT status ( 22,23 ). G ) 12-HETE generated by 12-lipoxygenase ( 10 ).…”

Biomedical and Biological Mass Spectrometry

“…Progress in technologies such as computational chemistry, robotics and biotechnology have contributed to this acceleration. Since MS has been a powerful tool for studying drug metabolism and disposition, [7][8][9][10][11][12] and the dynamics of endogenous biologically active substances, [58][59][60][61][99][100][101] it has also contributed to the greater speed in developing new therapeutics. Although GC/MS has played an important role in these studies, [124][125][126][127] various derivatizations are usually required to move the target compound into the gas-phase.…”

“…Therefore, chromatographic separation is required and especially important for the development of accurate quantitation methods for endogenous biologically active substances. 99,101 For highly selective analysis, the MS/MS instrument, which can perform the selected reaction monitoring analysis, is very useful, and can perform a highly sensitive quantitative determination. However, the same product ion spectrum pattern can be obtained from stereoisomers.…”