Dudman N P, Guo X W, Crooks R, Xie L, Silberberg J S
Center for Thrombosis and Vascular Research, University of New South Wales, Prince Henry Hospital, Little Bay, NSW, Australia.
Clin Chem. 1996 Dec;42(12):2028-32.
The recognition of homocysteine as a vascular risk factor has led to increased clinical interest in assaying plasma homocysteine concentrations. Our aim was to improve the reliability of a widely used assay based on HPLC of the fluorescent 7-benzo-2-oxa-1, 3-diazole-4-sulfonic acid (SBD) derivative. We found that SBD derivatives of homocysteine, cysteine, and N-acetylhomocysteine were highly unstable in light but essentially stable in the dark for several hours at either 0 degree C or 25 degrees C. As our primary calibrator, we chose homocystine added to human serum for more consistent results than homocysteine or homocystine in an aqueous buffer. N-acetylcysteine was effective as an internal recovery standard. We observed a previously unreported peak with a prolonged elution time in some plasma samples from subjects who had ingested methionine. Our findings suggest improvements in this and other assay procedures for plasma homocysteine.
同型半胱氨酸被确认为一种血管危险因素，这使得临床对检测血浆同型半胱氨酸浓度的兴趣增加。我们的目的是提高基于高效液相色谱法（HPLC）检测荧光7-苯并-2-恶唑-1,3-二氮杂萘-4-磺酸（SBD）衍生物的一种广泛使用的检测方法的可靠性。我们发现，同型半胱氨酸、半胱氨酸和N-乙酰同型半胱氨酸的SBD衍生物在光照下极不稳定，但在0℃或25℃黑暗环境中数小时内基本稳定。作为我们的主要校准物，我们选择添加到人体血清中的同型胱氨酸，以获得比在水性缓冲液中使用同型半胱氨酸或同型胱氨酸更一致的结果。N-乙酰半胱氨酸作为内标回收率标准有效。我们在摄入蛋氨酸的受试者的一些血浆样本中观察到一个洗脱时间延长的先前未报告的峰。我们的研究结果表明，这种以及其他血浆同型半胱氨酸检测方法需要改进。
