title: Pyrocatechol violet in pharmaceutical analysis. Part I. A spectrophotometric method for the determination of some beta-lactam antibiotics in pure and in pharmaceutical dosage forms.
abstract: A fairly sensitive, simple and rapid spectrophotometric method for the determination of some beta-lactam antibiotics, namely ampicillin (Amp), amoxycillin (Amox), 6-aminopenicillanic acid (6APA), cloxacillin (Clox), dicloxacillin (Diclox) and flucloxacillin sodium (Fluclox) in bulk samples and in pharmaceutical dosage forms is described. The proposed method involves the use of pyrocatechol violet as a chromogenic reagent. These drugs produce a reddish brown coloured ion pair with absorption maximum at 604, 641, 645, 604, 649 and 641 nm for Amp, Amox, 6APA, Clox, Diclox and Flucolx, respectively. The colours produced obey Beer's law and are suitable for the quantitative determination of the named compounds. The optimization of different experimental conditions is described. The molar ratio of the ion pairs was established and a proposal for the reaction pathway is given. The procedure described was applied successfully to determine the examined drugs in dosage forms and the results obtained were comparable to those obtained with the official methods.
authors.affiliation: Department of Chemistry, Faculty of Science, Benha University, Benha, Egypt.
authors.forename: A S
authors.initials: AS
authors.lastname: Amin
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis*; D001557:Benzenesulfonates / Q000737:chemistry*; D002021:Buffers; D002214:Capsules; D004396:Coloring Agents / Q000737:chemistry*; D004304:Dosage Forms; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D019999:Pharmaceutical Solutions; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D047090:beta-Lactams
chemical_list: D000900:Anti-Bacterial Agents; D001557:Benzenesulfonates; D002021:Buffers; D002214:Capsules; D004396:Coloring Agents; D004304:Dosage Forms; D007202:Indicators and Reagents; D019999:Pharmaceutical Solutions; D047090:beta-Lactams; C009134:pyrocatechol violet