Department of Analytical Chemistry, Mansoura University, Mansoura 35516, Egypt.
J Fluoresc. 2010 Mar;20(2):463-72. doi: 10.1007/s10895-009-0568-6. Epub 2009 Nov 27.
A sensitive, simple and selective spectrofluorimetric method was developed for the determination of Lamotrigine (LMT) in pharmaceutical formulations and biological fluids. The method is based on reaction of LMT with o-phthalaldehyde in presence of 2-mercaptoethanol in borate buffer of pH 9.8 to yield a highly fluorescent derivative that is measured at 448 nm after excitation at 337 nm. The different experimental parameters affecting the development and stability of the reaction product were carefully studied and optimized. The fluorescence-concentration plot was rectilinear over the range of 0.1-1.0 microg ml(-1) with lower limit of detection (LOD) 0.02 microg ml(-1) and limit of quantification (LOQ) 0.06 microg ml(-1) respectively. The proposed method was successfully applied to the the analysis of commercial tablets. Statistical comparison of the results obtained by the proposed and reference method revealed no significant difference in the performance of the two methods regarding the accuracy and precision respectively. The proposed method was further extended to the in-vitro and in-vivo determination of the drug in spiked and real human plasma. The mean percentage recoveries in spiked and real human plasma (n = 3) were 95.78 +/- 1.37 and 90.93 +/- 2.34 respectively. Interference arising from co-administered drugs was also studied. A proposal for the reaction pathway with o-phthalaldehyde was postulated.
建立了一种灵敏、简单和选择性的荧光分光光度法，用于测定药物制剂和生物体液中的拉莫三嗪（LMT）。该方法基于在硼酸缓冲液（pH 9.8）中，LMT 与邻苯二醛在 2-巯基乙醇存在下反应，生成一种高度荧光的衍生物，在 337nm 激发后在 448nm 处测定。仔细研究并优化了影响反应产物形成和稳定性的不同实验参数。荧光-浓度曲线在 0.1-1.0μg ml(-1)范围内呈线性，检测限（LOD）为 0.02μg ml(-1)，定量限（LOQ）为 0.06μg ml(-1)。该方法成功应用于商业片剂的分析。与参考方法相比，所提出方法的结果的统计比较表明，两种方法在准确性和精密度方面均无显著差异。该方法进一步扩展到了在体外和体内测定药物在加标和真实人血浆中的含量。加标和真实人血浆中的平均回收率（n = 3）分别为 95.78 ± 1.37%和 90.93 ± 2.34%。还研究了共存药物引起的干扰。提出了与邻苯二醛反应的途径假设。
