ABSTRACT
A spectrodensitometric method is described for the determination of the components of two analgesic mixtures. For the first mixture (paracetamol-ascorbic acid-caffeine-phenylephrine), the pharmaceutically active components were separated from each other and closely related degradation products and impurities on high-performance thin-layer chromatography (F254) plates using methylene chloride-ethyl acetate-ethanol-formic acid (3.5 + 2 + 4 + 0.5) and methylene chloride-ethyl acetate-ethanol (5 + 5 + 1) as the developing systems. The other mixture (phenazone-phenacetin-caffeine) was separated efficiently from the degradation products using the same plates and acetonitrile-chloroform (1 + 1) as the mobile phase. The proposed method was used to determine these mixtures in commercial tablets.
Subject(s)
Analgesics/analysis , Chromatography, High Pressure Liquid , Acetaminophen/analysis , Antipyrine/analysis , Ascorbic Acid/analysis , Caffeine/analysis , Phenacetin/analysis , Phenylephrine/analysisSubject(s)
Flufenamic Acid/analysis , Mefenamic Acid/analysis , Capsules , Spectrophotometry , SuspensionsABSTRACT
A colorimetric method is proposed for determination of terbutaline sulfate, orciprenaline sulfate, and their dosage forms. The suggested method depends on nitrosation of the 2 drugs by using sodium nitrite and hydrochloric acid. Addition of sodium hydroxide increases the intensity of the color developed. The difference between absorption values measured in acid and alkaline media is taken as a measure of concentration. Variables were carefully studied and optimized. Results for both compounds adhered to Beer's law over the range 2-28 micrograms/mL. The method has proved to be accurate and precise for analysis of pharmaceutical dosage forms.
