Determination of Content and Entrapment Efficiency of Ropivacaine Hydrochloride-loaded Multivesicular Liposomes / 中国药师

ABSTRACT

Objective:To establish a determination method for the content and entrapment efficiency of ropivacaine hydrochloride-loaded multivesicular liposomes. Methods: The separation of the multivesicular liposomes from the free drug was achieved by low-speed centrifugation. The concentration of ropivacaine hydrochloride in the supernatant and the multivesicular liposomes was determined by HPLC, and the entrapment efficiency was calculated. Results: The linear range of ropivacaine hydrochloride was 1. 0-80. 0μg· ml-1(r=0. 999 8). The average recovery was 99. 95% and RSD was 0. 72%(n=9). The content and entrapment efficiency of three batches of ropivacaine hydrochloride-loaded multivesicular liposomes was within the range of 99. 1%-100. 3% and 80. 06%-82. 14%, respectively. Conclusion:The method is simple and accurate, and can be used in the determination of content and entrapment efficien-cy of ropivacaine hydrochloride-loaded multivesicular liposomes.