title: Development and validation of a stability-indicating micellar liquid chromatographic method for the determination of timolol maleate in the presence of its degradation products.
abstract: A stability-indicating micellar liquid chromatographic (MLC) method was developed and validated for the quantitative determination of timolol maleate (TM) in the presence of its degradation products resulting from accelerated degradation in a run time not more than 8 min. TM was subjected to stress conditions of hydrolysis (including alkaline, acidic and thermal hydrolysis) and oxidation. An isocratic, rapid and mobile phase saving the micellar LC method was developed with a BioBasic phenyl column (150 × 1.0 mm, 5 µm particle size) and a micellar mobile phase composed of 0.1 M sodium dodecyl sulfate, 10% of 1-propanol and 0.1% of triethylamine in 0.035 M ortho-phosphoric acid. The flow rate of the mobile phase was 0.1 mL/min. UV detection was adjusted at 298 nm and performed at room temperature. The method has been validated according to the International Conference on Harmonisation guidelines. The method is successfully applied for the determination of TM in bulk powder and pharmaceutical dosage form.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Helwan University, Ain Helwan, Cairo 11790, Egypt.
authors.forename: Mohamed S
authors.initials: MS
authors.lastname: Rizk
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Cairo University, Kasr El Aini Street, Cairo 11562, Egypt.
authors.forename: Hanan A
authors.initials: HA
authors.lastname: Merey
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Helwan University, Ain Helwan, Cairo 11790, Egypt.
authors.forename: Shereen M
authors.initials: SM
authors.lastname: Tawakkol
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Helwan University, Ain Helwan, Cairo 11790, Egypt monanabil@helwan.edu.eg dr.monanabil@gmail.com.
authors.forename: Mona N
authors.initials: MN
authors.lastname: Sweilam
mesh_terms: D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D004355:Drug Stability; D016014:Linear Models; D009883:Ophthalmic Solutions / Q000032:analysis / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013999:Timolol / Q000032:analysis* / Q000737:chemistry*
chemical_list: D009883:Ophthalmic Solutions; D013999:Timolol