Flow-injection fluorimetric determination of 1,4-benzodiazepines in pharmaceutical formulations after acid hydrolysis

• Published in: Journal of pharmaceutical and biomedical analysis Vol. 20; no. 1; pp. 357 - 362
• Main Authors: Dolejšová, J., Solich, P., Polydorou, Ch.K., Koupparis, M.A., Efstathiou, C.E.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.06.1999; Elsevier Science
• Subjects: 1,4-benzodiazepines; Analysis; Anti-Anxiety Agents - analysis; Autoanalysis; Benzodiazepines - analysis; Biological and medical sciences; Calibration; Diazepam; Diazepam - analysis; Flow injection; Flow Injection Analysis; Fluorimetry; General pharmacology; Hydrogen-Ion Concentration; Hydrolysis; Indicators and Reagents; Medical sciences; Nitrazepam; Nitrazepam - analysis; Oxazepam; Oxazepam - analysis; Pharmaceutical analysis; Pharmacology. Drug treatments; Regression Analysis; Spectrometry, Fluorescence; Spectrophotometry, Ultraviolet; Nitrazepam; Pharmaceutical analysis; Fluorimetry; Oxazepam; 1,4-benzodiazepines; Diazepam; Flow injection; Hydrolysis; Acid reaction; Investigation method; Quality control; Dosage form; Benzodiazepine derivatives; Tablet; Fluorescence spectrometry; Quantitative analysis; Automated processing
• ISSN: 0731-7085; 1873-264X
• DOI: 10.1016/S0731-7085(99)00064-3

A simple, rapid and fully automated flow injection method with fluorimetric detection after hydrolysis with H 2SO 4 in ethanolic or methanolic medium at room temperature has been developed for the determination of 1,4-benzodiazepines (oxazepam, diazepam and nitrazepam) in pharmaceutical formulations. The calibration curves are linear in the ranges (mg ml −1) of oxazepam (0.025–0.150), diazepam (0.010–0.125) and nitrazepam (0.010–0.150), with detection limits of 0.01, 0.005 and 0.005 mg ml −1, respectively, and RSD (1% ( n=10). The measurement throughput is 60 h −1 using a 200-μl sample volume obtained by the direct dissolution of formulations in alcohol.