Solubility of carbon dioxide in three lipid-based biocarriers

Effect of Chemical Structure of Solid Lipid Matrix on Its Melting Behavior and Volumetric Expansion in Pressurized Carbon Dioxide

“…Previously, a similar melting behavior was reported by Ciftci and Temelli (2014) for tristearin, monostearin, and stearic acid (C18) in pressurized CO2 where melting point stayed constant in Region 2. In another study, a slight increase in the melting point was observed in the Region 2 starting from approximately 100 bar for mixtures of saturated fatty acids with carbon chains from C12 to C18 (de Sousa et al, 2006). Table 3 presents the melting point depression of FHSO and its mixtures with SO-MAG in pressurized CO2 measured at Point B.…”

Phase equilibria and physical properties of CO2-saturated cocoa butter mixtures at elevated pressures

“…It was found that CO 2 -saturated cocoa butter starts to melt at 21 • C and is completely molten at 23 • C. The measured values correspond to the literature values if the experimental accuracy is taken into account. It is common to observe a slight increase in the melting point of CO 2 -saturated fats and oils at higher pressures [15]. This is attributed to the competing effects of the increase in melting point due to a higher hydrostatic pressure and the decrease in the melting point due to the dissolution of CO 2 .…”

Study of the Effect of Pressure on Melting Behavior of Saturated Fatty Acids in Liquid or Supercritical Carbon Dioxide

“…In general, supercritical carbon dioxide (SCCO 2 ) is an excellent solvent for many nonpolar (and some polar) low molecular weight compounds and selected polymers, such as amorphous fluoropolymers and silicones. , However, the solubility of numerous pharmaceutically significant excipients such as fatty acids in liquid carbon dioxide (LCO 2 ) or SCCO 2 is very low and usually requires the addition of a cosolvent. Conversely, the solubility of SCCO 2 in many polymers, fats, and fat derivatives is substantial and it acts as a plasticizer which causes a depression in melting ( T m ) or glass transition ( T g ) temperatures. − The melting point of a pharmaceutical excipient is a crucial physical property which determines its appropriateness in various pharmaceutical processes and applications . LCO 2 and SCCO 2 are known to alter the melting points of various polymers and ionic salts. , Dissolution of CO 2 increases the free volume of an excipient by dissolving into the intermolecular spaces and causing a substantial reduction in T m or T g .…”

“…Dissolved CO 2 also reduces the viscosity of molten excipients which improves mixing, blending and flow characteristics of the melt . Moreover, it can also alter various other physical properties such as density, diffusivity and swollen volume of an excipient. , The depression in melting point allows organic solvent-free processing at low temperatures. Particles from gas saturated solution (PGSS) processes can be successfully performed at lower temperatures if the reduction in T m or T g of an excipient has been determined.…”