Preferential solvation of acetaminophen in ethanol + water solvent mixtures according to the inverse kirkwood-buff integrals method
The preferential solvation parameters, i.e., the differences between the local mole fraction of solvents around the solute and those for the bulk co-solvent mixtures in solutions of acetaminophen in ethanol + water binary mixtures were derived from their thermodynamic properties by means of the inve...
| Authors: | , , |
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| Format: | article |
| Status: | Published version |
| Publication Date: | 2013 |
| Country: | Colombia |
| Institution: | Universidad Nacional de Colombia |
| Repository: | Repositorio UN |
| Language: | Spanish |
| OAI Identifier: | oai:repositorio.unal.edu.co:unal/49747 |
| Online Access: | https://repositorio.unal.edu.co/handle/unal/49747 http://bdigital.unal.edu.co/43235/ http://bdigital.unal.edu.co/43235/2/ |
| Access Level: | Open access |
| Keyword: | acetaminofeno etanol solubilidad integrales inversas de Kirkwood-Buff IKBI solvatación preferencial acetaminophen ethanol solubility inverse Kirkwood-Buff integrals preferential solvation |
| Summary: | The preferential solvation parameters, i.e., the differences between the local mole fraction of solvents around the solute and those for the bulk co-solvent mixtures in solutions of acetaminophen in ethanol + water binary mixtures were derived from their thermodynamic properties by means of the inverse Kirkwood-Buff integrals (IKBI) method. It is found that acetaminophen is sensitive to solvation effects, so the preferential solvation parameter δxE,A, is negative in water-rich and ethanol-rich mixtures but positive in co-solvent compositions from 0.24 to 0.73 in mole fraction of ethanol. It is conjecturable that in water-rich mixtures the hydrophobic hydration around the aromatic ring and methyl group present in the drug plays a relevant role in the solvation. The more solvation by ethanol in mixtures of similar co-solvent compositions could be due mainly to polarity effects. Finally, the preference of this drug for water in ethanol-rich mixtures could be explained in terms of the bigger acidic behavior of water molecules interacting with the hydrogen-acceptor groups present in acetaminophen such as the carbonyl group. |
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