Azithromycin is a 15-membered ring macrolide antibiotic. According to the United States Pharmacopeia and the National Formulary (USP 39-NF 34*), analysis of azithromycin should be carried out with a column filled with L67 packing material and meets following requirements. The Asahipak ODP-50 4E confirmed the requirements were met.

System suitability requirements:
　Resolution of azithromycin and azaerythromycin A: ≥ 3.0
　Relative standard deviation (RSD): ≤ 1.1%
　Tailing factor of azithromycin: 0.8 to 1.5

*The version at the time of the application acquisition.


Sample : 10 μL
Azithromycin
Azaerythromycin A
dissolved in 6.7 g/L Dibasic potassium phosphate aq. (pH8.0 adjusted with phosphoric acid)/CH₃CN=40/60

Column       : Shodex Asahipak ODP-50 4E (4.6 mm I.D. x 250 mm)
Eluent       : 6.7 g/L Dibasic potassium phosphate aq. (pH11.0 adjusted with 10 M KOH)
               /CH3CN=40/60
Flow rate    : 1.0 mL/min
Detector     : UV (210 nm)
Column temp. : 40 °C