Nourooz-Zadeh J, Gopaul N K, Barrow S, Mallet A I, Anggård E E
Department of Medicine, University College London, UK.
J Chromatogr B Biomed Appl. 1995 May 19;667(2):199-208. doi: 10.1016/0378-4347(95)00035-h.
Recently, it has been reported that a series of prostaglandin F2-like compounds (F2-isoprostanes) are produced in vivo during peroxidation of arachidonic acid by a mechanism independent of the cyclooxygenase pathway. Of these, 8-epi-PGF2 alpha is shown to be a potent vasoconstrictor. We describe an improved method for analysing F2-isoprostanes in biological fluids. The method involves solid-phase extraction on an octadecylsilane (C18) and an aminopropyl (NH2) cartridge. After conversion to pentafluorobenzyl ester and trimethylsilyl ether derivatives, F2-isoprostanes are analysed by negative-ion chemical ionization mass spectrometry using tetradeuterated PGF2 alpha as the internal standard. The limit of detection of the assay was 10 pg/ml, with a coefficient of variation ranging from 9.4 to 15.1%. Analysis of plasma samples from healthy volunteers (n = 7) revealed no quantifiable levels of free (unesterified) 8-epi-PGF 2 alpha. However, the plasma samples contained 58 to 166 pg/ml of 8-epi-PGF2 alpha when analyzed for the total (sum of free and esterified) F2-isoprostanes. The main advantages of the method lie in the improved recovery, gas chromatographic separation and speed compared to existing techniques.
最近有报道称，一系列前列腺素F2样化合物（F2-异前列腺素）在体内由花生四烯酸过氧化产生，其机制独立于环氧化酶途径。其中，8-表-前列腺素F2α被证明是一种有效的血管收缩剂。我们描述了一种分析生物体液中F2-异前列腺素的改进方法。该方法包括在十八烷基硅烷（C18）和氨丙基（NH2）柱上进行固相萃取。在转化为五氟苄酯和三甲基硅醚衍生物后，以四氘代前列腺素F2α作为内标，通过负离子化学电离质谱法分析F2-异前列腺素。该测定方法的检测限为10 pg/ml，变异系数在9.4%至15.1%之间。对健康志愿者（n = 7）的血浆样本进行分析，未发现可量化水平的游离（未酯化）8-表-前列腺素F2α。然而，当分析总（游离和酯化之和）F2-异前列腺素时，血浆样本中含有58至166 pg/ml的8-表-前列腺素F2α。与现有技术相比，该方法的主要优点在于回收率提高、气相色谱分离效果好以及速度快。
