Preparation And Preliminary Study On Biological Characters Of Ornidazole Slow-Release Membranes

Objective: l.To introduce the preparation and quality control methods of the ornidazole slow-release membranes which take CM-chitosan as carriers.2. To primarily evaluate the biological activities of the membranes by exploring the toxicology, biocompatibility, in vivo release rate and antibacterial activities. Methods: l.The quantity of ornidazole, the uniformity and the in vitro release rate of ornidazole from the membranes were determined by ultraviolet spectrophotometry. 2.Forty Wistar rats were divided into 3 groups. The first group consisted of 12 Wistar rats whose gingivae were bluntly separated from the teeth to establish the periodontal pocket models. The animals were respectively treated with abdominal injection of ornidazole (A-group) and local application of the ornidazole slow release membranes (L-group). Gingival crevicular fluid (GCF) was gained at 0.5, 1, 2, 3, 4h in A-group and 24h, 48h, 5d in L-group to examine the concentration of ornidazole. In the second group, the lower lips of 12 rats were sewed into 12 pockets and the pockets were immited wih extracting solution of the ornidazole membrane, formaldehyde and normal saline respectively once per day. The specimens were examined histologically 7 days later. The third group included 16 rats whose dorsal muscles were implanted with the membranes or silk threads. The specimens were examined histologically lweek and 2, 4, 6 weeks later respectively. 3. 40 guinea pigs were denuded of dorsal fur 24h before the experiment. And the denuded areas were spreaded with extracting solution of the ornidazole membrane, extracting solution of the membrane without ornidazole, normal saline and 2, 4-dintro-chlorobenzene in the 1st day and the 7th, 14th, 28th day. Calculate the irritability rates. 4.The in vitro antibacterial activity against Streptococcus mutans and Fusobacterium nucleatum was observed on solid culture medium. Results: l.The maximum absorption of ornidazole solution was observed at the point of 318nm wavelength when scanned by the UV- spectrophotometer. The average of the content of ornidazole in the membrane was 99.69% of the marked quantity. RSD=0.8%. And the membrane is uniform and stable. 13.9% ornidazole was released from the membrane in the initial 10 minutes and it was still detectable 10 hours later. 2. The animal experiments showed the membranes were not irritative to the oral mucosa and it showed no irritability for guinea pig skin. It was found that the tissue reaction of the...