OBJECTIVETo prepare Dange Mingmu in-situ forming eye gel.

METHODThe viscosity of Dange Mingmu in-situ forming eye gel was tested by adopting poloxamer 407 and 188 as thermosensitive materials, and optimizing by uniform design. Drug release in vitro was studied using a novel membraneless model. Eye irritation experiments were performed with rabbits. The duration of residence time in rabbit eyes was observed using fluorescence tracer method.

RESULTThe gelation temperature of in-situ thermosensitive gel was lowered as the P407 concentration increased. In a certain range, the gelation temperature slowly increased with the increase of P188's concentration, and the effect of P407 was greater than that of P188. The optimized concentration of P407/P188 was 19%/1%. Based the adjusted concentration, Dange Mingmu in-situ forming eye gel. was converted into freely flowing liquid below 26.9 degrees C and became gel at 34.5 degrees C after being diluted with STF. In line with zero-order kinetics, drug release in vitro depends on gel erosion. The residence time on the surface of eyes was proved to be relatively long was and nonirritant.

CONCLUSIONUniform design is available for optimizing the formulation of thermosensitive gel for eye. The gel satisfies the requirement for ophthalmic application, and is expected to be applied in clinical practice in the future.