Preparation and in vitro Release of Norfloxacin Thermosensitive in Situ Gel for Vaginal Use / 中国药师

ABSTRACT

Objective:To prepare norfloxacin thermosensitive in situ gel and investigate its in vitro drug release behavior. Meth-odsPoloxamer 407 and poloxamer 188 were used as the matrix of norfloxacin thermosensitive in situ gel,and the gel was prepared by a cold dissolving method. The formula was optimized by a central composite design-response surface method. In vitro drug release be-havior of norfloxacin thermosensitive in situ gel was studied as well. Results:Within a certain concentration range, the gelation tem-perature decreased gradually with the amount increase of poloxamer 407, and that increased gradually with the amount increase of poloxamer 188. The optimal formula was as followsthe concentration of poloxamer 407 was 20.6%(w/v),and that of poloxamer 188 was 5.7%(w/v),which obtained suitable gelling temperature. The release of norfloxacin from the thermosensitive in situ gel reached up to (87.5% ± 5.4% 7 in 6 h. Conclusion: Norfloxacin thermosensitive in situ gel has excellent temperature sensitivity, and can slow down the drug release,which shows potential use for vaginal drug delivery system.