Study On The Preparation Of Ornidazole For Sustained Release Of Nonnasality

Ornidazole is one kind of the third generation new nitryl imidazole classderivative after metronidazole and tinidazole. It has the good function ofanti-anaerobe and the anti-infusorium. At present, the preparation of ornidazole as thefourth kind of new medicine on the market has the very strong resistance bacteriaactiveness in vitro to the nonnasality superiority disease germ. There are somedosage-forms of ornidazole in our country, such as the tablet, the gel, the capsule, theemulsion, the suppository and so on, which are usually used in dermatologydepartment, gynecology and obstetrics department. Only a few preparations such asthe tablet, the liquor and the cataplasma are used in the nonnasality department. Sincethe tablet and other preparations are often used several times in one day, it isinconvenient to be used and the blood concentration is volatile, "peak and valley"happens frequently.Sustained release preparation can achieve a long period of drug release andmaintain an adequate blood concentration. Compared with conventional preparation,it can significantly reduce the number of eating drugs and reduce the burden onpatients and easy to achieve the treatment. In this paper the preparations of sustainedrelease formulations of ornidazole containing microspheres, films and rods wereprepared. The results showed that the releasing cycle is about one week. D,L-lactide/glycollide copolymer (PLGA), which is one of the biodegradable materialswas used as the excipient, which can act in the nonnasality inflammation directly andmaintain constant effective drugs concentration for a long period of time as well asavoid many side effects induced by systemic administration.Ornidazole loaded PLGA microspheres were prepared by solvent evaporationtechnique in this study. Single factor design is used to optimize the conditions for theprocess. The preparation method was optimized and the final optimized conditionswere: the concentration of PVA, ornidazole and PLGA is 0.03g/ml, 0.02g/ml and0.04g/ml, respectively and the rotate speed is 1000rpm, which was stabile anddependable. The particle size distribution and appearance were evaluated by usingoptic microscope. The microspheres had smooth surface and the average size was23.97μm. The loading and encapsulation rate of ornidazole were detected by the ultraviolet spectrophotometry, which was (23.75±0.07)% and (86.36±0.25)%respectively. The film and the rod preparation of ornidazole were also made and theloading as well as release behavior was determined by ultraviolet spectrophotometry.The ornidazole release of macrospheres in vitro showed that there was an initial burstrelease followed by the stable and sustained release for about 7days.In conclusion, the biodegradable polymer system provides the promising newalternative for the delivery of ornidazole microspheres to produce prolonged actingtime and decrease side effects. It can reduce the burden on patients and be easy toimplement treatment.