Accelerated Release Testing Method and Preparation of Docetaxel Capsule Tension Ring / 中国药学杂志

OBJECTIVE: To develop the accelerated release test method of docetaxel capsule tension ring and optimize its formulation. METHODS: The effects of ethanol concentration in the medium (0%, 5%, 10%) and temperature (37 and 45 ℃) on the release rate of docetaxel capsule tension ring were investigated, and the correlation regression equation between the accelerated release rate and the long-term release was established. Then, the best prescription was screened out with the accelerated release test method. RESULTS: The drug release rate of these preparations could be increased by four times under the accelerated conditions, i.e., using pH 7.4 phosphate buffer solution containing 5% ethanol as the release medium and operating at (45±0.5)℃. The accelerated release and long-term release were fitted the best using binomial model (y=0.004 6x2+0.437 4x+9.683 7, r2=0.998 4). The preparation using PLGA5050 (60K-100K=1:1, W/W) with drug-loading of 30% released drug stably and sustainedly for 30 d, and its release behavior was consistent with Peppas equation drug release model. CONCLUSION: Accelerated release testing can be employed as a rapid screening test to facilitate the formulation optimization of docetaxel capsule tension ring. This preparation has been proven to have sustained-release characteristics, suggesting a good clinical application prospect.

In vitro accelerated release of triptorelin acetate microspheres and the in vivo/in vitro correlation / 国际药学研究杂志

Objective To establish an in vitro accelerated release method of triptorelin acetate microspheres with good in vi-tro/in vivo correlation(IVIVC). Methods The in vivo release of triptorelin acetate from microspheres was obtained by residual method in rats. Influences of pH value,concentration of ethanol,temperature,rotation speed and concentration of antiseptic on the in vitro accel-erated release were studied,then the correlation between in vitro accelerated release and in vivo release of the microspheres was estab-lished by adjusting the release conditions. Results The in vitro accelerated release medium of triptorelin acetate microspheres composed of 15%ethanol solution(containing 0.06%Tween 80 and 0.1%benzalkonium chloride)at 55℃with rotating rate of 200 r/min. The cumulative release of triptorelin acetate from microspheres was 87.35%at 30 h under accelerated release condition,equivalent to in vivo release for 30 days. The established in vitro accelerated release had a good correlation with that of in vivo(y=0.8845x+12.4510, R2=0.9938). Conclusion The in vitro accelerated release of triptorelin acetate microspheres could correlate well with in vivo release and has a potential application in rapid and effective evaluation of triptorelin acetate microspheres.

An in vitro accelerated approach based on in vivo release to assess thymopentin release from PLGA microspheres / 国际药学研究杂志

Objective To establish an accelerated method that has good correlations with in vivo release data for formulation optimization and quality control purposes of thymopentin-loaded poly(DL-lactide-co-glycolide)(PLGA)microspheres. Methods In vivo thymopentin release from the microspheres was studied in Sprague-Dawley rats and relevant cumulative release curves were plotted. Key factors including release medium types,ethanol concentrations,surfactant concentrations and heating temperature were investigated for the in vitro accelerated release. The conditions for accelerated release were optimized to make the accelerated release cures fit the in vivo release well. The final optimized accelerated release method was validated in other two formulations. Results The final optimized accelerated release conditions were: 20% hydro-alcoholic solutions (V/V)and 0.06% Tween 80 (W/V)as the release media,gradient heating program (0-1 h at 40 °C,1-6 h at 45 °C and 6-30 h at 50 °C)as the media heating method. After fitted with the in vivo release curves,the correlation constant r2 of (8,13 and 28)×103 PLGA microspheres was 0.9783,0.9886 and 0.9780,respectively. Conclusion By introducing alcohol into the release media and applying gradient heating program,the reported accelerated method can be used in the formulation optimization and quality control of thymopentin-loaded PLGA microspheres.

An in vitro accelerated approach based on in vivo release to assess thymopentin release from PLGA microspheres / 国际药学研究杂志

Objective To establish an accelerated method that has good correlations with in vivo release data for formulation optimization and quality control purposes of thymopentin-loaded poly (DL-lactide-co-glycolide) (PLGA) microspheres. MethodsIn vivo thymopentin release from the microspheres was studied in Sprague-Dawley rats and relevant cumulative release curves were plotted. Key factors including release medium types, ethanol concentrations, surfactant concentrations and heating temperature were investigated for the in vitro accelerated release. The conditions for accelerated release were optimized to make the accelerated release cures fit the in vivo release well. The final optimized accelerated release method was validated in other two formulations. ResultsThe final optimized accelerated release conditions were: 20% hydro-alcoholic solutions (V/V) and 0.06% Tween 80 (W/V) as the release media, gradient heating program (0-1 h at 40 °C, 1-6 h at 45 °C and 6-30 h at 50 °C) as the media heating method. After fitted with the in vivo release curves, the correlation constant r2 of (8, 13 and 28)×103 PLGA microspheres was 0.9783, 0.9886 and 0.9780, respectively. ConclusionBy introducing alcohol into the release media and applying gradient heating program, the reported accelerated method can be used in the formulation optimization and quality control of thymopentin-loaded PLGA microspheres.