Analytical Chemistry Department, Faculty of Pharmacy, Minia University, Minia, Egypt.
Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Assiut University, Assiut, Egypt.
Spectrochim Acta A Mol Biomol Spectrosc. 2018 Apr 15;195:215-222. doi: 10.1016/j.saa.2018.01.077. Epub 2018 Feb 1.
A new, selective and sensitive spectrofluorimetric method was designed for the quantitation of doxazosin (DOX), terazosin (TER) and alfuzosin (ALF) in their dosage forms and human plasma. The method adopts efficient derivatization of the studied drugs with ortho-phthalaldehyde (OPA), in the presence of 2-mercaptoethanol in borate buffer (pH9.7) to generate a highly fluorescent isoindole derivatives, which can strongly enhance the fluorescence intensities of the studied drugs, allowing their sensitive determination at 430nm after excitation at 337nm. The fluorescence-concentration plots were rectilinear over the ranges (10.0-400.0) ng/mL. Detection and quantification limits were found to be (0.52-3.88) and (1.59-11.76) ng/mL, respectively. The proposed method was validated according to ICH guidelines, and successfully applied for the determination of pharmaceutical preparations of the studied drugs. Moreover, the high sensitivity of the proposed method permits its successful application to the analysis of the studied drugs in spiked human plasma with % recovery (96.12±1.34-100.66±0.57, n=3). A proposal for the reaction mechanism was presented.
一种新的、选择性和灵敏的荧光分光光度法被设计用于定量测定 doxazosin（DOX）、terazosin（TER）和 alfuzosin（ALF）在其剂型和人血浆中的含量。该方法采用邻苯二甲醛（OPA）对研究药物进行高效衍生化，在硼酸缓冲液（pH9.7）中加入 2-巯基乙醇，生成强荧光的异吲哚衍生物，可强烈增强研究药物的荧光强度，允许在 337nm 激发下在 430nm 处进行灵敏测定。荧光浓度曲线在（10.0-400.0）ng/mL 范围内呈线性。检测限和定量限分别为（0.52-3.88）和（1.59-11.76）ng/mL。该方法根据 ICH 指南进行了验证，并成功应用于研究药物制剂的测定。此外，该方法的高灵敏度允许其成功应用于加标人血浆中研究药物的分析，回收率为 96.12±1.34-100.66±0.57（n=3）。提出了一个反应机制的建议。
