title: Determination of benzalkonium chloride in viscous ophthalmic drops of azithromycin by high-performance liquid chromatography.
abstract: A high-performance liquid chromatography (HPLC) system was used in the reversed phase mode for the determination of benzalkonium chloride (BKC) in azithromycin viscous ophthalmic drops. A Venusil-XBP(L)-C(18) (150 mmx4.6 mm, 5 microm) column was used at 50 degrees C. The mobile phase consisted of a mixture of methanol-potassium phosphate (16:5, v/v). Two sample preparation methods were compared. The results suggested that, compared with an extraction procedure, a deproteinization procedure was much quicker and more convenient. Using the deproteinization procedure for sample preparation, calibration curves were linear in the range 5.0 to approximately 50 microg/ml. The within-day and inter-day coefficients of variation were less than 10%. The average recoveries were determined as 96.70%, 98.52%, and 97.96% at concentrations of 10.0, 30.0, and 50.0 microg/ml, respectively. Variability in precision did not exceed 5%. In conclusion, this HPLC method using a simple sample treatment procedure appears suitable for monitoring BKC content in azithromycin viscous ophthalmic drops.
authors: Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China.
authors: Yan
authors: Y
authors: Shen
authors: Sheng-jie
authors: SJ
authors: Xu
authors: Shi-chun
authors: SC
authors: Wang
authors: Jia-sheng
authors: JS
authors: Tu
mesh_terms: D017963:Azithromycin / Q000032:analysis*; D001548:Benzalkonium Compounds / Q000737:chemistry*; D002138:Calibration; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002845:Chromatography / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008956:Models, Chemical; D009883:Ophthalmic Solutions / Q000737:chemistry*; D015203:Reproducibility of Results; D014783:Viscosity
chemical_list: D001548:Benzalkonium Compounds; D009883:Ophthalmic Solutions; D017963:Azithromycin