Thermodynamic study of the solubility of acetaminophen in propylene glycol + water cosolvent mixtures

Journal of the Brazilian Chemical Society

Jackson A. Jiménez¹  Fleming Martínez¹ 

[1] ,Universidad Nacional de Colombia Departamento de Farmacia Bogotá D.C. ,Colombia

关键词: acetaminophen;    solubility;    solution thermodynamics;    activity coefficients;   

DOI  :  10.1590/S0103-50532006000100018

来源: SciELO

【 摘 要 】

Based on van't Hoff and Gibbs equations the thermodynamic functions Gibbs energy, enthalpy, and entropy of solution, mixing and solvation of acetaminophen in propylene glycol + water (PG + W) cosolvent mixtures, were evaluated from solubility data determined at several temperatures. The solubility was greater at 100% of PG at all temperatures studied. The solvation of this drug in the mixtures increases as the PG proportion is also increased founding a maximum at 70% of PG. From 10% up to 20% of PG and from 70% up to 100% of PG, entropy driving was found, while from pure water up to 10% of PG and from 20% up to 70% of PG, enthalpy driving was found. These facts can be explained in terms of water-structure loss, and a diminishing in the energy required for cavity formation in the solvent, for mixtures from 30% up to 70% of PG.

【 授权许可】

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