Studies On The Preparation And Clinical Application Of Amoxicillin Microcapsules

Amoxicillin is a broad-spectrum bacterium antibiotics which was widely used on veterinary clinical application. The absorption, distribution and metabolism in the body of amoxicillin or its ordinary dosage were relatively quickly, the time in gastrointestinal residence was shorter and need many times to give medicine to maintain its antibacterial action everyday. The study of amoxicillin micro-capsule preparation could extending the retention time of drug in the stomach to relieving treatment effect, and play a better curative effect, and to reduce dosing frequency.The amoxicillin micro-capsule was made by fluidized bed coating method, the characterization of the amoxicillin micro-capsule was detected and its pharmacodynamics research was conducted on the recommendation of sea cucumber Vibrio splendidus. The amoxicillin micro-capsule was observed by the electron microscope and scanning electron microscopy (SEM), with micrometer measuring micro-capsule particle size, particle size distribution, and then calculate the average value; Ultraviolet spectrophotometry(UV) was used to make standard curve drawing of amoxicillin, then encapsulation efficiency and drug loading capacity of amoxicillin micro-capsule were detected. Contrast examination of the micro-capsule made by in vitro release, and stability of amoxicillin micro-capsule was detected by further studied through accelerated test. Finally, sea cucumber were used as experimental animals, treatment was given after artificial infection of Vibrio splendidus each group,60sea cucumber were affected to3groups at random, and there were20on each group. Group Ⅰ with normal breeding, amoxicillin powder was scattered into the water at Group Ⅱ, according to the2g/m3water, amoxicillin micro-capsule was scattered into the water at GroupⅢ, according to the22g/m3water (including2g/m3of amoxicillin active pharmaceutical ingredients), group Ⅱ, Ⅲ continuous dosing7d, medicine was given three times a day. After delivery, maintain normal feeding every day,2days later started to change water20%every day, the survived sea cucumber were counted of each experimental group every day, after7days the total number of live sea cucumber of each group were statistics, and the survival rate was calculated.The results show that by electron microscope and particle size measurement, micro-capsule was white, the distribution was relatively uniform, through the determination of micro-capsule size distribution results, the average particle size of it was about10microns, particle size distribution in the4-12microns within the scope of the micro-capsule was more than80%of the total; Amoxicillin precision and the recovery experiment results show that RSD of the intra-day was less than1.0%, RSD of the inter-day was less than2.0%, the recovery rate was98.81%～100.10%, and the envelopment rate and drug loadings reached91.07%and9.11%respectively; Amoxicillin powder was released more than90%after20min, however, the micro-capsule was only released about20%at the same time; Amoxicillin micro-capsule was still white under60℃after10days, the appearance had no obvious change, the content of amoxicillin was reduced by1.67%after5days, and3.0%after10days.The color of amoxicillin micro-capsule was deeper under25℃and relative humidity of90%after10days, the content of amoxicillin was reduced by3.4%after5days, and5.3%after10days. The color of amoxicillin micro-capsule was little deeper in the45001x±500lx,the content of amoxicillin was reduced by1.25%after5days, and3.0%after10days;Pharmacodynamic tests show without drug treatment sea cucumber were all dead after5days, after7days, survival rate of amoxicillin powder reached70%and amoxicillin micro-capsule group was as high as80%.Electron microscope and particle size measurement results show that the laboratory preparation of amoxicillin capsule had good shape and particle size distribution was relatively uniform. Precision and recovery experiment results show that using the ultraviolet method to determinate the content of amoxicillin, coating rate and drug loadings was accurately and feasible; The high coating rate and drug loading capacity showed that amoxicillin was relatively completed be coated, and the micro-capsule could accord with the requirement of clinical drug use; In vitro release test show that release rate of amoxicillin micro-capsule was decreased significantly, and has a slow release effect; Stability experiment showed that amoxicillin capsule is stable to heat and light, sensitive to moisture, so it should be paid attention to keep away from moisture; Pharmacodynamics experiment shows that the amoxicillin micro-capsule was better than amoxicillin powder treatment effect, the advantages in clinical was obvious.