Kato Kayoko, Silva Manori J, Brock John W, Reidy John A, Malek Nicole A, Hodge Carolyn C, Nakazawa Hiroyuki, Needham Larry L, Barr Dana B
Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA.
J Anal Toxicol. 2003 Jul-Aug;27(5):284-9. doi: 10.1093/jat/27.5.284.
We developed a highly sensitive method for the quantitative detection of nine phthalate ester metabolites in human serum. This method requires denaturation of the serum enzymes immediately after blood collection to avoid the hydrolysis of the contaminant diester parent compounds introduced during blood collection and storage. Before analysis, the samples were subjected to an enzymatic deconjugation to hydrolyze the glucuronidated phthalate monoesters and a solid-phase extraction to isolate the monoesters from other serum components. The extracts were analyzed using reversed-phase high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry. The limits of detection of all nine phthalate monoesters in serum were in the low nanogram-per-milliliter range (0.6-1.3 ng/mL). Stable isotope-labeled internal standards for all analytes were used to improve precision and for recovery corrections. This highly selective method permits the analysis of phthalate monoesters without interferences resulting from the hydrolysis of the ubiquitous contaminant phthalate diesters by serum enzymes. In addition, it allows the direct measurement of the active phthalate monoester metabolites reportedly responsible for the reproductive and developmental toxicity of certain phthalates.
我们开发了一种高灵敏度方法，用于定量检测人血清中的九种邻苯二甲酸酯代谢物。该方法要求在采血后立即使血清酶变性，以避免水解采血和储存过程中引入的污染物二酯母体化合物。分析前，对样品进行酶解结合以水解葡萄糖醛酸化的邻苯二甲酸单酯，并进行固相萃取以从其他血清成分中分离单酯。提取物采用反相高效液相色谱-电喷雾电离-串联质谱进行分析。血清中所有九种邻苯二甲酸单酯的检测限均在低纳克/毫升范围内（0.6-1.3 ng/mL）。使用所有分析物的稳定同位素标记内标来提高精密度并进行回收率校正。这种高选择性方法允许分析邻苯二甲酸单酯，而不会受到血清酶水解普遍存在的污染物邻苯二甲酸二酯所产生的干扰。此外，它还允许直接测量据报道对某些邻苯二甲酸酯的生殖和发育毒性负责的活性邻苯二甲酸单酯代谢物。
