Sailstad J M, Findlay J W
Wellcome Research Laboratories, Burroughs Wellcome Company, Research Triangle Park, North Carolina 27709.
Ther Drug Monit. 1991 Sep;13(5):433-42. doi: 10.1097/00007691-199109000-00008.
An immunofluorometric assay (IFA) has been developed for the potential antiepileptic agent, lamotrigine (Lamictal). The assay involves competition between lamotrigine free in solution and bound to a bovine thyroglobulin conjugate on the surface of microtiter strip wells for a limited amount of polyclonal lamotrigine antisera. The end-point of this reaction, which indicates the concentration of lamotrigine present in the solution under analysis, is detected by adding Eu(3+)-labelled anti-rabbit IgG, followed by an enhancement solution to produce a fluorescent product. Thus, the higher the concentration of lamotrigine in the sample, the less intense the fluorescence produced. The assay displays minor cross-reactivity (0.05%) by the major glucuronide metabolite (in humans) and moderate cross-reactivity (2.7%) by a minor N-oxide metabolite (in rats) of the parent drug. No interference from these sources in the analysis of plasma samples from clinical trials was demonstrated by comparative sample analysis by IFA and high-performance liquid chromatography. Intraassay accuracy and precision were excellent, greater than 90% and less than 5% coefficient of variation (CV), while interassay accuracy was greater than 95% and interassay precision (CV) was 8.8-17.0%. This assay is suitable for analysis of lamotrigine in plasma samples collected during clinical trials.
已开发出一种免疫荧光分析法（IFA）用于检测潜在的抗癫痫药物拉莫三嗪（利必通）。该分析方法涉及溶液中游离的拉莫三嗪与微量滴定条孔表面结合于牛甲状腺球蛋白偶联物上的拉莫三嗪，竞争有限量的多克隆拉莫三嗪抗血清。通过加入铕（3+）标记的抗兔IgG，然后加入增强溶液以产生荧光产物，来检测该反应的终点，此终点指示分析溶液中拉莫三嗪的浓度。因此，样品中拉莫三嗪的浓度越高，产生的荧光强度越低。该分析方法对主要葡萄糖醛酸代谢物（在人体内）显示出轻微的交叉反应性（0.05%），对母体药物的次要N-氧化物代谢物（在大鼠体内）显示出中等程度的交叉反应性（2.7%）。通过IFA和高效液相色谱法对比较样品进行分析，未证明这些来源对临床试验血浆样品分析有干扰。批内准确度和精密度极佳，变异系数（CV）大于90%且小于5%，而批间准确度大于95%，批间精密度（CV）为8.8 - 17.0%。该分析方法适用于分析临床试验期间采集的血浆样品中的拉莫三嗪。
