scholarly journals Enhancement of the dissolution rate and bioavailability of fenofibrate by a melt-adsorption method using supercritical carbon dioxide

2012 ◽  
pp. 5565 ◽  
Author(s):  
Sung-Joo Hwang ◽  
Kwang-Ho Cha ◽  
KJ Cho ◽  
MS Kim ◽  
Hee Jun Park ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Dissolution Rate ◽  
Adsorption Method ◽  
Supercritical Carbon

Crystal Structure Changes of γ-cyclodextrin After the SEDS Process in Supercritical Carbon Dioxide Affect the Dissolution Rate of Complexed Budesonide

2007 ◽  
Vol 24 (6) ◽  
pp. 1058-1066 ◽  
Author(s):  
Tarja Toropainen ◽  
Teemu Heikkilä ◽  
Jukka Leppänen ◽  
Laura Matilainen ◽  
Sitaram Velaga ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Dissolution Rate ◽  
Structure Changes ◽  
Supercritical Carbon

scholarly journals Melt Amorphisation of Orlistat with Mesoporous Silica Using a Supercritical Carbon Dioxide: Effects of Pressure, Temperature, and Drug Loading Ratio and Comparison with Other Conventional Amorphisation Methods

Pharmaceutics ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 377
Author(s):  
Heejun Park ◽  
Kwang-Ho Cha ◽  
Seung Hyeon Hong ◽  
Sharif Md Abuzar ◽  
Eun-Sol Ha ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Mesoporous Silica ◽  
Dissolution Rate ◽  
Supercritical Fluid ◽  
Pore Volume ◽  
Total Pore Volume ◽  
Content Uniformity ◽  
Mass Ratio ◽  
Supercritical Carbon

The aim of this work was to develop an amorphous orlistat-loaded mesoporus silica formulation using the melt-amorphisation by supercritical fluid (MA-SCF) and to investigate the effects of pressure and temperature on the pharmaceutical properties of the developed formulation. In addition, the effect of orlistat mass ratio to the mesoporus silica was also evaluated. The carbon dioxide was used as a supercritical fluid, and Neusilin®UFL2 was selected as the mesoporous silica. For comparison with conventional amorphisation methods, orlistat formulations were also prepared by solvent evaporation and hot melt methods. Various pharmaceutical evaluations including differential scanning calorimetry, powder X-ray diffraction, scanning electron microscopy, specific surface area, total pore volume, and content uniformity were performed to characterise the prepared orlistat formulation. The melting point depression and the solubility of orlistat in supercritical carbon dioxide (SC-CO2) were selected for the interpretation of evaluated results in relation to temperature and pressure. The total pore volume of the prepared orlistat-loaded mesoporus silica decreased with an increasing density of SC-CO2 to about 500 g/L at a constant temperature or pressure. From these results, it was suggested that increasing the density of SC-CO2 to about 500 g/L could result in the easier penetration of CO2 into molten orlistat and lower viscosity, hence facilitating the introduction and loading of orlistat into the pores of Neusilin®UFL2. However, when the density of SC-CO2 increased to more than 500 g/L, the total pore volume increased, and this may be due to the release out of orlistat from the pores of Neusilin®UFL2 by the increased orlistat solubility in SC-CO2. Interestingly, as the total pore volume decreased by the filling of the drug, the drug crystallinity decreased; hence, the dissolution rate increased. Furthermore, it was shown that the most desirable mass ratio of Neusilin®UFL2:orlistat for the amorphisation was 1:0.8 at an optimised supercritical condition of 318 K and 10 MPa. Compared with other amorphisation methods, only the sample prepared by the MA-SCF method was in pure amorphous state with the fastest dissolution rate. Therefore, it was concluded that the amorphous orlistat-loaded mesoporus silica prepared using MA-SCF under optimised conditions was more advantageous for enhancing the dissolution rate of orlistat than other conventional amorphisation methods.

Dissolution rate measurements for resist processing in supercritical carbon dioxide

2002 ◽  
Author(s):  
Victor Q. Pham ◽  
Gina L. Weibel ◽  
Nagesh G. Rao ◽  
Christopher K. Ober
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Dissolution Rate ◽  
Supercritical Carbon
Sign in / Sign up

Export Citation Format

Share Document