title: Rapid and sensitive HPLC method for the simultaneous determination of dorzolamide hydrochloride and timolol maleate in eye drops with diode-array and UV detection.
abstract: A rapid and sensitive HPLC method has been developed for the simultaneous determination of dorzolamide hydrochloride and timolol maleate. The drugs were monitored with a diode-array detector at two fixed wavelengths (lambda = 250.0 nm for dorzolamide hydrochloride and 300.0 nm for timolol maleate). Liquid chromatography was performed on a RP-YMC pack ODS A-132 C18 (5 microm, 15 cm x 6.0 mm) column and the mobile phase consisted of an acetonitrile: phosphate buffer (pH 2.5): methanol (5:85:10 v/v/v) mix and a flow rate of 1.2 ml x min(-1). The linearity of the method ranged between 4.0-45.0 microg x ml(-1) for dorzolamide hydrochloride and and 2.0-20.6 microg x ml(-1) for timolol maleate in binary mixture. The procedure was successfully applied to the determination of these compounds in pharmaceutical preparations and gave a high recovery, good accuracy and precision without any interference by the excipients.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Ankara University, Tandoğan-Ankara,Turkey. erk@pharmacy.ankara.edu.tr
authors.forename: N
authors.initials: N
authors.lastname: Erk
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000032:analysis*; D002138:Calibration; D002257:Carbonic Anhydrase Inhibitors / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D007202:Indicators and Reagents; D009883:Ophthalmic Solutions; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet; D013449:Sulfonamides / Q000032:analysis*; D013876:Thiophenes / Q000032:analysis*; D013999:Timolol / Q000032:analysis*
chemical_list: D000319:Adrenergic beta-Antagonists; D002257:Carbonic Anhydrase Inhibitors; D007202:Indicators and Reagents; D009883:Ophthalmic Solutions; D013449:Sulfonamides; D013876:Thiophenes; D013999:Timolol; C062765:dorzolamide