Determination of content and encapsulation efficiency of leuprolideacetate microspheres
Objective To establish a determination method for leuprolide acetate microspheres. Methods HPLC was performed on Inertsil ODS-SP (150×4.6 mm×5μm) with mobile phase consist of 0.1 mol/L of Ammonium Dihydrogen Phosphate(adjust its pH to 7.00±0.05 with Ammonium Hydroxide) and Acetonitrile in ratio of 3:1(V/V),and the flow rate was 1.0 mL/min.The wavelength was 220 nm and column temperature was 30℃. The injection volume was 20 μL. Results The linear range of leuprolide acetate was 20.0-160.0μg/mL (r=0.9999) with an average recovery of 99.80%,RSD=0.63%(n=9). Conclusion The method of HPLC was accurate,reliable and specific, which could be used to determinate the assay of leuprolide acetate microspheres and for quality control of microspheres.