Solubility of drugs in non-aqueous systems is very important in understanding the partitioning and transport behavior. The present study was undertaken to evaluate the entropic and enthalpic contribution to activity coefficient of organic compounds (polycyclic aromatic hydrocarbons, aliphatic acids, aliphatic alcohols etc.) in non-aqueous solvents. The activity coefficient can be written as: ln γ₁ = ln γ₁ᶜ + ln γ₁ʳ where superscript "c" and "r" denote entropic (combinatorial) and enthalpic contribution respectively. We selected three solvent systems: benzene, triolein and octanol. The different models considered in this study were Flory-Huggins, Scatchard-Hildebrand, UNIQUAC combinatorial and UNIFAC residual. A combination of Flory-Huggins and Scatchard-Hildebrand which accounts for both the entropic and enthalpic effects gives the best predictions in all the solvents considered.
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/184667 |
| Date | January 1989 |
| Creators | Mishra, Dinesh Shyamdeo. |
| Contributors | Yalkowsky, Samuel H. |
| Publisher | The University of Arizona. |
| Source Sets | University of Arizona |
| Language | English |
| Detected Language | English |
| Type | text, Dissertation-Reproduction (electronic) |
| Rights | Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. |
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