A concise review of HPLC, LC-MS and LC-MS/MS methods for determination of azithromycin in various biological matrices.

Azithromycin is one of the best selling antibiotics in the world. It belongs to the new macrolide family of azalides. It is derived from erythromycin and it differs from erythromycin in having a 15-membered ring and a methyl substituted nitrogen inserted at the 9a position in the aglycone ring. This structural modification confers favourable microbiological and pharmacokinetic characteristics on azithromycin and greater acid stability compared with erythromycin. It is mainly used to treat respiratory infections, sexually transmitted diseases, cutaneous and soft-tissue infections, etc. This review provides a comprehensive overview of various HPLC, LC-MS and LC-MS/MS methods for quantitation of azithromycin in different biological matrices. In addition, it provides general information on extraction steps, internal standard selection, conditions for chromatographic separation, brief validation data and applicable conclusions for reported methods in a defined pattern.