Solubility of Dexamethasone in Supercritical Carbon Dioxide with and without a Cosolvent

Abstract

The solubility of dexamethasone, a synthetic glucocorticoid, in supercritical CO 2 and together with 3.0 mol % ethanol as a cosolvent was measured at different temperatures (313.2, 318.2, and 323.2) K and pressures ranging from (10.0 to 25.0) MPa by a static analytical method. The obtained solubility of dexamethasone was between 1.19·10 −6 and 1.52·10 −6 in pure supercritical CO 2 and between 1.97·10 −6 and 2.98·10 −6 in supercritical CO 2 with a cosolvent. The experimental data in supercritical CO 2 in the absence and presence of a cosolvent were correlated using four density-based semiempirical models, that is, Chrastil, Kumar and Johnston, Bartle, and Meńdez-Santiago and Teja models. The results indicated that the Kumar and Johnston model gave a better correlated result than the other three with an average absolute relative deviation [AARD (%)] value lower than 2.15 %.

Solubility of Solids in Sub- and Supercritical Fluids: A Review 2010–2017

“…In the case of β-carotene, solubility and adsorption equilibria in propane were investigated, while Jin et al reported the solubility of 4-aminosalicylic acid in 1,1,1,2-tetrafluoroethane (R134a). , Generally, hydrophobic and polar substances are almost insoluble in SC CO 2 . To enhance the solubility of these substances, cosolvents like ethanol, ethyl acetate, and acetone can be used. − …”

Solubility of sinensetin and isosinensetin from Cat’s Whiskers (Orthosiphon stamineus) leaves in ethanol-assisted supercritical carbon dioxide extraction: experimental and modeling

“…Therefore, the increase in extraction temperature enhances diffusivity and solute-solvent interactions and also reduces the viscosity and surface tension of the solvent which allows it to diffuse more easily in the plant matrix. Tang et al (2014) reported a similar finding whereby an increase in temperature from 313.2 to 323.2 K enhanced the dexamethasone solubility. This is because a robust polar interaction and hydrogen bonding between modifier (ethanol) and dexamethasone is detected as the temperature rose.…”

Sustained release of dexamethasone from drug‐loadingPLGAscaffolds with specific pore structure fabricated by supercritical CO2foaming

“…And the amount of dexamethasone in drug‐loading porous PLGA scaffolds kept going down due to the dissolution in water in the leaching out of NaCl. Generally, the loss of dexamethasone in the process of scCO 2 foaming could be negligible because the solubility of dexamethasone was only 1.19 × 10 −6 –1.52 × 10 −6 mol/mol in scCO 2 . Even though a large amount of dexamethasone was lost in preparation of drug‐loading PLGA microspheres in this work, co‐dissolving in dichloromethane is still a practical method to incorporate dexamethasone into PLGA phase homogeneously, and dexamethasone‐loading capacity of porous PLGA scaffolds could be regulated by changing initial dexamethasone or NaCl addition to satisfy the requirements of clinical practice.…”