How to Cite
Downloads
Métricas Alternativas
Dimensions
Abstract
Based on van't Hoff and Gibbs equations the thermodynamic functions free energy, enthalpy, and entropy of solution, mixing and solvation of acetaminophen in ethanol + water cosolvent mixtures, were evaluated from solubility data determined at several temperatures. The solubility was greater at 90% m/m of ethanol at all temperatures studied. This result shows clearly the cosolvent effect present in this system. The solvation of this drug in the mixtures increases as the ethanol proportion is also increased. By means of enthalpy-entropy compensation analysis, a more complex behavior for solution was found with respect to that exposed previously in literature. From 0% up to 10% m/m of ethanol and from 90% up to 100% of ethanol, entropy driving was found, while from 20% up to 60% of ethanol, enthalpy driving was found. These facts would be explained in terms of a losing of water-structure in addition to a diminishing in the energy required for cavity formation in the solvent for mixtures from 20% up to 60% of ethanol. Nevertheless in the ethanol-rich mixtures the intermolecular mechanisms involved in the solution process should be more complex including other physicochemical considerations.
Keywords
References
Baena, Y., Pinzón, J.A., Barbosa, H., Martínez, F. 2004. Temperature dependence of the solubility of some acetanilide derivatives in several organic and aqueous solvents. Phys. Chem. Liquids 42: 603-13.
Bevington, P.R. 1969. “Data Reduction and Error Analysis for the Physical Sciences”, McGraw-Hill Book Co., New York, pp. 56-65.
Budavari, S., O’Neil, M.J., Smith, A., Heckelman, P.E., Obenchain, Jr., J.R., Gallipeau, JAR., D’Arecea, M.A. 2001. “The Merck Index, An Encyclopedia of Chemicals, Drugs, and Biologicals”, 13th edition, Merck & Co., Inc., Whitehouse Station, NJ, p. 10.
Bustamante, P., Romero, S., Reillo, A. 1995. Thermodynamics of paracetamol in amphiprotic and amphiprotic-aprotic solvent mixtures. Pharm. Sci. 1: 505-7.
Bustamante, P., Romero, S., Peña, A., Escalera, B., Reillo, A. 1998. Nonlinear enthalpy-entropy compensation for the solubility of drugs in solvent mixtures: paracetamol, acetanilide and nalidixic acid in dioxane-water. J. Pharm. Sci. 87: 1590-6.
Dearden, J.C. 1972. Nature of acetaminophen-antipyrine complex. J. Pharm. Sci. 61: 1661-3.
Etman, M.A., Naggar, V.F. 1990. Thermodynamics of paracetamol solubility in sugar-water cosolvent systems. Int. J. Pharm. 58: 177-84.
Fedors, R.F. 1974. A method for estimating both the solubility parameters and molar volumes of liquids. Polym. Eng. Sci. 14: 147-54.
Garzón, L.C., Martínez, F. 2004. Temperature-solubility dependence for ibuprofen in some organic and aqueous solvents. J. Solution Chem. 33: 1379-95.
Grant, D.J.W., Mehdizadeh, M., Chow, A.H.L., Fairbrother, J.E. 1984. Nonlinear van’t Hoff solubility-temperature plots and their pharmaceutical interpretation. Int. J. Pharm. 18: 25-38.
Hildebrand, J.H., Prausnitz, J.M., Scott, R.L. 1970. “Regular and Related Solutions”, Van Nostrand Reinhold, New York.
Hollenbeck, R.G. 1980. Determination of differential heat of solution in real solutions from variation in solubility with temperature. J. Pharm. Sci. 69: 1241-2.
Jiménez, F., Martínez, F. 1995. A strategy for systematic selection of cosolvent vehicles in the design of homogeneous liquid pharmaceutical dosage forms. Rev. Col. Cienc. Quím. Farm. 24:19-23.
Karger, BL., Zinder, L.R., Eon, C. 1976. An expanded solubility parameter treatment for classification and use of chromatographic solvents and adsorbents. Parameters for dispersion, dipole and hydrogen bonding interactions. J. Chromatography 125: 71-88.
Krug, R.R., Hunter, WG., Grieger, RA. 1976. Enthalpy-entropy compensation. 2. Separation of the chemical from the statistical effects. J. Phys. Chem. 80: 2341-51.
Leffler J.E., Grunwald E. 1963. “Rates and Equilibria of Organic Reactions”, Wiley, New York.
Lund, W. 1994. “The Pharmaceutical Codex”, 12th edition, The Pharmaceutical Press, London, pp. 987-93.
Manzo, R.H., Ahumada, A.A. 1990. Effects of solvent medium on solubility. V. Enthalpic and entropic contributions to the free energy changes of di-substituted benzene derivatives in ethanol:water and ethanol:cyclohexane mixtures. J. Pharm. Sci. 79: 1109-15.
Martin, A., Bustamante, P., Chun, AHC. 1993. “Physical Pharmacy: Physical Chemical Principles in the Pharmaceutical Sciences”, 4th edition, Lea & Febiger, Philadelphia.
Martínez F, Gómez, A. 2001. Thermodynamic study of the solubility of some sulfonamides in octanol, water, and the mutually saturated solvents. J. Solution Chem. 30: 909-23.
Pérez DC, Guevara CC, Cárdenas CA, Pinzón JA, Barbosa HJ, Martínez, F. 2003. Solubility and displacement volumes of acetaminophen in binary mixtures formed by propylene glycol, ethanol, and water at 25.0 °C. Rev. Col. Cienc. Quím. Farm. 32: 116-36.
Perlovich GL, Kurkov SV, Bauer-Brandl, A. 2003. Thermodynamics of solutions II: Flurbiprofen and diflunisal as models for studying solvation of drug substances. Eur. J. Pharm. Sci. 19: 423-32.
Perlovi ch GL, Kurkov SV, Kinchin AN, Bauer-Brandl A. 2004. Thermodynamics of solutions III: Comparison of the solvation of (+)-naproxen with other NSAIDs. Eur. J. Pharm. Biopharm. 57: 411-20.
Roberts II LJ, Morrow JD. 2001. Analgesic-antipyretic and antiinflammatory agents and drugs employed in the treatment of gout, in: “Goodman & Gilman’s. The Pharmacological Basis of Therapeutics”, 10th edition, International Edition, Edited by Hardman JG, Limbird LE, Gilman AG. McGraw-Hill, New York, pp. 703-5.
Romero S, Reillo A, Escalera B, Bustamante P. 1996. The behavior of paracetamol in mixtures of amphiprotic and amphiprotic-aprotic solvents: Relationship of solubility curves to specific and nonspecific interactions. Chem. Pharm. Bull. 44: 1061-64.
Romero S, Bustamante P, Escalera B, Cirri M, Mura P. 2004. Characterization of the solid phases of paracetamol and phenamates at equilibrium in saturated solutions. J. Thermal Anal. Calorimetry 77: 541-54.
Rosenstein-Ster, E. 2004. “Diccionario de Especialidades Farmacéuticas”, 32a edición, Thompson P.L.M., S.A., Bogotá.
Rubino, JT. 1988. Cosolvents and cosolvency, in: “Encyclopedia of Pharmaceutical Technology”, Edited by Swarbrick, J. and Boylan, J.C. Marcel Dekker, New York, Vol 3, pp. 375-98.
Schoemaker DP, Garland, GW. 1968. “Experimentos de Fisicoquímica”, Unión Tipográfica Editorial Hispano Americana, México, pp. 43-4.
Tomlinson, E. 1983. Enthalpy-entropy compensation analysis of pharmaceutical, biochemical and biological systems.
US Pharmacopeia, 23rd edition, 1994. The United States Pharmacopeial Convention, Rockville, MD, pp. 16-7.
Williams D, Wilson D, Storey R, Basford, P. 2004. Vapour pressure determination of pharmaceutical powders, in: 7th International Conference/Workshop on Pharmacy and Applied Physical Chemistry at the University of Innbruck, Austria; URL: http://www. euroestar-science.org/conferences/abstrsph7/wilson.pdf
Yalkowsky, SH. 1999. “Solubility and Solubilization in Aqueous Media”, American Chemical Society and Oxford University Press, New York.
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Copyright (c) 2023 https://creativecommons.org/licenses/by-nc-nd/4.0