The Pharmaceutical Study Of Injectable Shen Mai Implants

Objective:Shen Mai injection has been used to improve and reduce the osteoarthritis symptoms in clinical setting and shown a good application prospect in China. This project has been based on the clinical application and research, and the temperature-sensitive in situ gel was prepared from Shen Mai extract and its formulation optimization, determination of index composition, preparation evaluation and performance of in vitro drug release has been done. Temperature-sensitive in situ gel was accurately and objectively evaluated in the existing basis of experiment.Methods:This project included the optimization of formulation, determination of index composition, preparation evaluation and performance of in vitro of drug release of Shen Mai.The formulation optimization study was composed of the preparation of the temperature-sensitive in situ gel by means of the cold dissolution method, processing with the optimization of many kinds of temperature-sensitive in situ gel matrix factor through single factor analysis method in order to confirm the best formulation.The determination method study involved the establishment of accurate and reliable determination method of Ginsenoside index composition Rb1through the High Performance Liquid Chromatography (HPLC).The formulation preparation evaluation study represented the establishment of quality evaluation criteria of Shen Mai temperature-sensitive in situ gel, and these criteria were composed of formulation appearance, pH value, and temperature of phase transition, time of phase transition, rheology, and viscosity recovery through heating up many times, content and stability investigation.The in vitro drug release performance study involved the investigation of in vitro release behavior of Shen Mai temperature-sensitive in situ gel and common Shen Mai extract using the dynamic dialysis method, and the results were fitted by the mathematical models to explore the mechanism of sustained release formulation as compared with the reference of solution of Shen Mai extract and Shen Mei injections.Results:The sustained release formulation optimization study had shown that the best formulation composition was17%P407:3%P188:6.12%Shen Mai extract:73.88%H2O (w:w:w:w).The index content determination had shown that the HPLC method was successfully developed and validated for determination of index content Ginseng saponins Rb1in Shen Mai temperature-sensitive in situ gel. Chromatographic separation was performed on a Kromasil-C18(250x4.6mm, Sμm) analytical column with Acetonitrile:Water (v/v) as mobile phase for Ginseng saponins Rb1,29%～33%for A between0-30min. Detection was performed using UV detector at the wavelength of203nm, the column temperature was30℃. the flow rate was1.0mL/min. The method for quantitative determination of Ginseng saponins Rb1showed to be linear over a range of0.01-1μg, the linear regression equation was y=294.47x-0.4019, r=0.9998. The method met the requirements of sample analysis, and was successfully applied to quality control study.The formulation quality control had shown that the establishment of quality evaluation criteria of Shen Mai temperature-sensitive in situ gel had been developed, and these criteria were composed of formulation appearance, pH value, and temperature of phase transition, time of phase transition, rheology, and viscosity recovery through heating up many times, content and stability investigation. Shen Mai temperature-sensitive in situ gel was brown, clarity and uniform solution at room temperature or4℃, and then changed brown, clarity and uniform semi-solid gel at37℃body temperature. The pH value, and temperature of phase transition, time of phase transition of Shen Mai gel were5.02at25℃,34.92℃,1579.52mPa-s,110.67s, respectively. Shen Mai temperature-sensitive in situ gel changed from Newtonian fluid to pseudoplastic fluid with increasing temperature, and viscosity recovery had good property with the reversible changes of both morphological appearance and gelling temperature through repeated cycle of heating and cooling. The accelerated test results showed that the index Ginseng saponins Rb1in Shen Mai temperature-sensitive in situ gel was basically stable for3months at25℃, and morphological appearance of gel was uniform with no stratification phenomena. The centrifuge test results showed that no stratification phenomena of Shen Mai temperature-sensitive in situ gel happened at the temperature conditions of25℃and37℃.The in vitro drug release performance study had shown that the in vitro release data of Shen Mai temperature-sensitive in situ gel could be fitted by the first order mathematical equation, and the characteristics of drug release showed that the index Ginseng saponins Rb1decreased slowly with non-constant speed in accordance with requirements of the sustained drug release system. The diffusion index of Ritger-Pappas equation was n=0.7485, which showed that the index content Ginseng saponins Rb1release mechanism of sustained formulation was synergy activity of matrix diffusion and skeleton dissolution (drug dissolution). Therefore, Ginseng saponins Rb1which was dispersed in polymer system dissolved out accompanying with skeleton dissolution process due to the certain intensity of gel system at37℃Conclusions:The preparation method of Shen Mai temperature-sensitive in situ gel was stable and viable, and the formulation quality could be controlled. Shen Mai temperature-sensitive in situ gel had shown the significant sustained release characteristics and had been able to achieve the complete release.