Department of Analytical Chemistry, Faculty of Pharmacy, University of Mansoura, 35516, Mansoura, Egypt.
Luminescence. 2011 Nov-Dec;26(6):670-9. doi: 10.1002/bio.1294. Epub 2011 Apr 13.
A highly sensitive and simple spectrofluorimetric method was developed for the determination of loratadine (LRT) and desloratadine (DSL) in their pharmaceutical formulations. The proposed method is based on investigation of the fluorescence spectral behaviour of LRT and DSL in a sodium dodecyl sulphate (SDS) micellar system. In aqueous solution of acetate buffer of pH 4.5, the fluorescence intensities of both LRT and DSL were greatly enhanced (240%) in the presence of SDS. The fluorescence intensity was measured at 438 nm after excitation at 290 nm for both drugs. The fluorescence-concentration plots were rectilinear over the range 0.05-2.0 µg/mL for both LRT and DSL, with lower detection limits of 5.13 × 10(-3) and 6.35 × 10(-3) µg/mL for LRT and DSL, respectively. The method was successfully applied to the analysis of the two drugs in their commercial tablets, capsules and syrups, and the results were in good agreement with those obtained with the official or comparison methods. The proposed method is specific for the determination of LRT in the presence of other co-formulated drugs, such as pseudoephedrine. The application of the proposed method was extended to stability studies of LRT and DSL after exposure to different forced degradation conditions, such as acidic, alkaline and oxidative conditions, according to ICH guidelines.
建立了一种测定药物制剂中氯雷他定（LRT）和地氯雷他定（DSL）的高灵敏度、简单的荧光分光光度法。该方法基于在十二烷基硫酸钠（SDS）胶束体系中研究 LRT 和 DSL 的荧光光谱行为。在 pH 4.5 的醋酸盐缓冲水溶液中，SDS 的存在极大地增强了 LRT 和 DSL 的荧光强度（240%）。对于两种药物，在 290nm 激发下，在 438nm 处测量荧光强度。对于 LRT 和 DSL，荧光浓度图在 0.05-2.0μg/mL 范围内呈线性，LRT 和 DSL 的检测限分别为 5.13×10^(-3)和 6.35×10^(-3)μg/mL。该方法成功地应用于两种药物在其商业片剂、胶囊和糖浆中的分析，结果与官方或比较方法获得的结果一致。该方法特异性强，可在存在其他共配制药物（如伪麻黄碱）的情况下测定 LRT。根据 ICH 指南，该方法的应用扩展到 LRT 和 DSL 在不同强制降解条件（如酸性、碱性和氧化条件）下的稳定性研究。
