Belal Fathalla, Ibrahim Fawzia, Sheribah Zainab, Alaa Heba
Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, University of Mansoura, Mansoura, Egypt.
Luminescence. 2017 Nov;32(7):1299-1306. doi: 10.1002/bio.3325. Epub 2017 May 18.
The present paper describes a developed and validated simple, highly sensitive and cost-effective spectrofluorometric method for determination of clonazepam (CNP). The proposed method depends on forming a highly fluorescent product through the reduction of CNP with Zn/HCl. The produced fluorophore exhibits a strong fluorescence at λ 350 nm after excitation at λ 250 nm. The use of carboxymethylcellulose (CMC) greatly enhanced the fluorescence intensity of the produced fluorophore to the extent of about 100%. Calibration curve showed good linear regression (r > 0.9998) within test ranges of 20-400 ng ml with a lower detection limit of 0.67 ng ml and lower quantification limit of 2.22 ng ml upon using CMC. The method was successfully applied to the analysis of CNP in its pharmaceutical formulations and the results were in agreement with those obtained using a reference method. Furthermore, the content uniformity testing of the tablets was also performed. The application of the proposed method was extended to determine CNP in spiked human plasma sample as a preliminary investigation and the results were satisfactory.
本文描述了一种已开发并经验证的简单、高灵敏度且经济高效的分光荧光法，用于测定氯硝西泮（CNP）。所提出的方法依赖于用锌/盐酸还原CNP形成一种高荧光产物。所产生的荧光团在250nm激发后，在350nm处呈现出强烈的荧光。使用羧甲基纤维素（CMC）极大地增强了所产生荧光团的荧光强度，增幅约为100%。校准曲线在20 - 400 ng/ml的测试范围内显示出良好的线性回归（r > 0.9998），使用CMC时检测限为0.67 ng/ml，定量限为2.22 ng/ml。该方法成功应用于其药物制剂中CNP的分析，结果与使用参考方法获得的结果一致。此外，还进行了片剂的含量均匀度测试。作为初步研究，所提出的方法的应用扩展到了加标人血浆样品中CNP的测定，结果令人满意。
