Determination of Spiramycin I and Its Primary Metabolite Neospiramycin I in Meat, Milk and Fish by HPLC

A simple and rapid method using HPLC for the determination of spiramycin I (major and most important component) and its metabolite, neospiramycin I, in meat, fish and milk has been developed. Neospiramycin I was obtained by acidic treatment of spiramycin I. The drugs were extracted with 1.2% metaphosphoric acid-methanol (5:5), and the extracts were cleaned up on a Bond Elut SCX (500mg) cartridge. The HPLC separation was performed on a Puresil 5C18 column (150×4.6mm i. d.) using 0.05mol/L phosphate buffer (pH 2.5) -acetonitrile (76:24) as the mobile phase at a flow rate of 0.5mL/min. The drugs were detected at 235nm. The calibration graphs were rectilinear from 2 to 50ng for both drugs. The recoveries of the drugs from meat, milk and fish at the level of 0.2μg/g were 80.3-85.3%, and detection limits were 0.05μg/g for both drugs.