Determination of erythromycin and related substances in enteric-coated tablet formulations by reversed-phase liquid chromatography.
An isocratic method for the identification and quantitation of erythromycin and related substances in enteric-coated tablet formulations using high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection at 205 nm is described. A novel method for sample preparation using a molecular weight centrifuge filter to reduce the interferences observed from polymeric tablet coating material is also presented. Erythromycin HPLC assays are best run at high pH; therefore, various polymer columns were evaluated. The resulting HPLC method that was developed has several advantages over current pharmacopeial assay methods for enteric-coated erythromycin tablets. Comparative data from both methods for the same batch of EryTab tablets are presented. The method can also be applied to various other erythromycin formulations, including particle-coated tablets, erythromycin stearate tablets, and erythromycin ethylsuccinate suspensions and fermentation broths. A C18 Polymeric column is used with a mobile phase composition of 0.02 M potassium phosphate dibasic buffer (pH 9): acetonitrile (60:40) and flow rate of 1 mL/min. This method is more sensitive, specific, and rugged than the pharmacopeial method.
Wardrop
J
J
Formulation Development Center, Department 4P7, Abbott Laboratories, Bldg. R1A, 1401 Sheridan Road, North Chicago, Illinois 60064-4000, USA. Wardrop@abbott.com
Ficker
D
D
Franklin
S
S
Gorski
R J
RJ
D002626:Chemistry, Pharmaceutical; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004355:Drug Stability; D004917:Erythromycin / Q000031:analogs & derivatives / Q000032:analysis* / Q000737:chemistry; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013608:Tablets, Enteric-Coated
D013608:Tablets, Enteric-Coated; D004917:Erythromycin