The behavior of bovine serum albumin (BSA) in water is scarcely studied, and the thermodynamic properties arising from the experimental measurements have not been reported. Intrinsic viscosity measurements are very useful in assessing the interaction between the solute and solvent. This work discussed in a simple determination of the enthalpy of BSA in aqueous solution when the concentration ranges from 0.2 to 36.71%？wt. and the temperature from 35 to C. The relationship between the concentration and intrinsic viscosity is determined according to the method of Huggins. The temperature increase reduces the ratio between inherent viscosity and concentration ( ). This is reflected in the Van't Hoff curve. Furthermore, this work proposes hydrodynamic cohesion value as an indicator of the degree of affinity of protein with water and thermodynamic implications in conformational changes. 1. Introduction Solubility is the ability of a substance to dissolve into another; it is given by the solubility constant which is in equilibrium with the solute excess or ions excess. Basic studies on proteins have focused on protein concentration, pH, ionic strength, polymeric additives, the dielectric properties of solvent and solvent mixtures, and effect temperature. In the case of proteins and polysaccharides, solubility studies are closely related to studies of gelation that try to determine the temperature and the concentration of gelation ( and ) (Djabourov) [1]. The conformational stability of a protein is determined by intramolecular factors and solvent interactions (hydration). Solubility is determined primarily by intermolecular effects (protein/protein), but, as proteins are solvated, the hydration effects are also involved in changes in solubility. Conformational changes (changes in functional activity) can be induced by changes in temperature, pressure, and the solvent medium. The technological performance of proteins depends critically on conformation, hydration (water-holding capacity), and solubility. Like other polymers, proteins can be characterized by their chain conformations. However, methods of polymer statistics cannot be applied to most proteins because they adopt specific (native) conformations under different physiological conditions. Since proteins are polyelectrolytes, their solubility behavior is governed largely by electrostatic (ionic) interactions. In determining charge/charge interactions, and values of individual amino acids play an important role (Franks) [2]. Barton [3] worked with solubility parameters, trying to explain their nature and
References
[1]
M. Djabourov, “Gelation. A review,” Polymer International, vol. 25, no. 3, pp. 135–143, 1991.
[2]
F. Franks, Solution Properties of Proteins, Elsevier, 1988.
[3]
A. F. M. Barton, “Applications of solubility parameters and other cohesion parameters in polymer science and technology,” Pure and Applied Chemistry, vol. 57, no. 7, pp. 905–912, 1985.
[4]
A. F. M. Barton, “Solubility parameters,” Chemical Reviews, vol. 75, no. 6, pp. 731–753, 1975.
[5]
C. M. Hansen, “The universality of the solubility parameter,” Industrial and Engineering Chemistry Product Research and Development, vol. 8, no. 1, pp. 2–11, 1969.
[6]
D. Mangarj, S. K. Bhatnagar, and S. B. Rath, “Cohesive-energy-densities of high polymers—part. III: estimation of C. E. D. by viscosity measurements,” Die Makromolekulare Chemie, vol. 67, no. 1, pp. 75–83, 1963.
[7]
A. E. Bozdogan, “A method for determination of thermodynamic and solubility parameters of polymers from temperature and molecular weight dependence of intrinsic viscosity,” Polymer, vol. 45, no. 18, pp. 6415–6424, 2004.
[8]
I. L. Shulgin and E. Ruckenstein, “Preferential hydration and solubility of proteins in aqueous solutions of polyethylene glycol,” Biophysical Chemistry, vol. 120, no. 3, pp. 188–198, 2005.
[9]
A. Guner, “The algorithmic calculations of solubility parameter for the determination of interactions in dextran/certain polar solvent systems,” European Polymer Journal, vol. 40, no. 7, pp. 1587–1594, 2004.
[10]
R. Ravindra, K. R. Krovvidi, and A. A. Khan, “Solubility parameter of chitin and chitosan,” Carbohydrate Polymers, vol. 36, no. 2-3, pp. 121–127, 1998.
[11]
X. P. Kong, J. Wang, C. J. Wang, and X. J. Wu, “Basicity, water solubility and intrinsic viscosity of carboxymethyl chitosan as a biofunctional material,” Advanced Materials Research, vol. 531, pp. 507–510, 2012.
[12]
B. Naskar, A. Dan, S. Ghosh, and S. P. Moulik, “Viscosity and solubility behavior of the polysaccharide inulin in water, water + dimethyl sulfoxide, and water + isopropanol media,” Journal of Chemical and Engineering Data, vol. 55, no. 7, pp. 2424–2427, 2010.
[13]
R. Brodersen, “Bilirubin. Solubility and interaction with albumin and phospholipid,” Journal of Biological Chemistry, vol. 254, no. 7, pp. 2364–2369, 1979.
[14]
P. Minghetti, F. Cilurzo, A. Casiraghi, and L. Montanari, “Application of viscometry and solubility parameters in miconazole patches development,” International Journal of Pharmaceutics, vol. 190, no. 1, pp. 91–101, 1999.
[15]
P. Bustamante, J. Navarro-Lupión, and B. Escalera, “A new method to determine the partial solubility parameters of polymers from intrinsic viscosity,” European Journal of Pharmaceutical Sciences, vol. 24, no. 2-3, pp. 229–237, 2005.
[16]
K. Adamska, A. Voelkel, and K. Heberger, “Selection of solubility parameters for characterization of pharmaceutical excipients,” Journal of Chromatography A, vol. 1171, no. 1-2, pp. 90–97, 2007.
[17]
E. Cohn, “The relation between the iso-electric point of a globulin and its solubility and acid combining capacity in salt solution,” Proceedings of the National Academy of Sciences of the United States of America, vol. 6, no. 5, pp. 256–263, 1920.
[18]
E. J. Cohn and J. L. Hendry, “Studies in the physical chemistry of the proteins: II. The relation between the solubility of casein and its capacity to combine with base. The solubility of casein in systems containing the protein and sodium hydroxide,” Journal of General Physiology, vol. 5, no. 5, pp. 521–554, 1923.
[19]
K. L. Shaw, G. R. Grimsley, G. I. Yakovlev, A. A. Makarov, and C. N. Pace, “The effect of net charge on the solubility, activity, and stability of ribonuclease Sa,” Protein Science, vol. 10, no. 6, pp. 1206–1215, 2001.
[20]
J. P. Schmittschmitt and J. M. Scholtz, “The role of protein stability, solubility, and net charge in amyloid fibril formation,” Protein Science, vol. 12, no. 10, pp. 2374–2378, 2003.
[21]
F. Ferreira Machado, J. S. R. Coimbra, E. E. Garcia Rojas, L. A. Minim, F. C. Oliveira, and R. D. C. S. Sousa, “Solubility and density of egg white proteins: effect of pH and saline concentration,” LWT—Food Science and Technology, vol. 40, no. 7, pp. 1304–1307, 2007.
[22]
K. Monkos, “Concentration and temperature dependence of viscosity in lysozyme aqueous solutions,” Biochimica et Biophysica Acta, vol. 1339, no. 2, pp. 304–310, 1997.
[23]
K. Monkos, “Viscosity analysis of the temperature dependence of the solution conformation of ovalbumin,” Biophysical Chemistry, vol. 85, no. 1, pp. 7–16, 2000.
[24]
M. L. Olivares, M. B. Peirotti, and J. A. Deiber, “Analysis of gelatin chain aggregation in dilute aqueous solutions through viscosity data,” Food Hydrocolloids, vol. 20, no. 7, pp. 1039–1049, 2006.
[25]
R. Curvale, M. Masuelli, and A. Perez Padilla, “Intrinsic viscosity of bovine serum albumin conformers,” International Journal of Biological Macromolecules, vol. 42, no. 2, pp. 133–137, 2008.
[26]
I. M. N. Sousa, P. J. Morgan, J. R. Mitchell, S. E. Harding, and S. E. Hill, “Hydrodynamic characterization of Lupin proteins: solubility, intrinsic viscosity, and molar mass,” Journal of Agricultural and Food Chemistry, vol. 44, no. 10, pp. 3018–3021, 1996.
[27]
J. L. Shen, “Solubility profile, intrinsic viscosity, and optical rotation studies of acid precipitated soy protein and of commercial soy isolate,” Journal of Agricultural and Food Chemistry, vol. 24, no. 4, pp. 784–788, 1976.
[28]
T. Arakawa and S. N. Timasheff, “Theory of protein solubility,” Methods in Enzymology, vol. 114, pp. 49–77, 1985.
[29]
J. Peters, All Albumin, Elsevier, 1993.
[30]
I. S. Haworth, Protein Solubility. Chemistry: Foundations and Applications, 2004, http://www.encyclopedia.com/doc/1G2-3400900422.html.
[31]
M. A. Masuelli, “Viscometric study of pectin. Effect of temperature on the hydrodynamic properties,” International Journal of Biological Macromolecules, vol. 48, no. 2, pp. 286–291, 2011.
[32]
O. Segarceanua and M. Leca, “Improved method to calculate Hansen solubility parameters of a polymer,” Progress in Organic Coatings, vol. 31, no. 4, pp. 307–310, 1997.
[33]
K. Monkos, “Viscosity of bovine serum albumin aqueous solutions as a function of temperature and concentration,” International Journal of Biological Macromolecules, vol. 18, pp. 61–68, 1996.
[34]
K. Monkos, “On the hydrodynamics and temperature dependence of the solution conformation of human serum albumin from viscometry approach,” Biochimica et Biophysica Acta, vol. 1700, no. 1, pp. 27–34, 2004.
[35]
F. Agostini, M. Vendruscolo, and G. G. Tartaglia, “Sequence-based prediction of protein solubility,” Journal of Molecular Biology, vol. 421, no. 2-3, pp. 237–241, 2012.
[36]
J. Jiang, Y. L. Xiong, and J. Chen, “pH shifting alters solubility characteristics and thermal stability of soy protein isolate and its globulin fractions in different pH, salt concentration, and temperature conditions,” Journal of Agricultural and Food Chemistry, vol. 58, no. 13, pp. 8035–8042, 2010.
[37]
J. I. Boye, I. Alli, and A. A. Ismail, “Interactions involved in the gelation of bovine serum albumin,” Journal of Agricultural and Food Chemistry, vol. 44, no. 4, pp. 996–1004, 1996.
[38]
A. H. Clark, G. M. Kavanagh, and S. B. Ross-Murphy, “Globular protein gelation—theory and experiment,” Food Hydrocolloids, vol. 15, no. 4–6, pp. 383–400, 2001.
[39]
D. H. G. Pelegrine and C. A. Gasparetto, “Whey proteins solubility as function of temperature and pH,” LWT—Food Science and Technology, vol. 38, no. 1, pp. 77–80, 2005.
[40]
K. H. van Holde, Physical Biochemistry, Prentice Hall, Englewood Cliffs, NJ, USA, 1971.
[41]
K. C. Fan, M. Song, and R. S. Lu, “Measurement system of tiny angle based on LED,” in Seventh International Symposium on Precision Engineering Measurements and Instrumentation, vol. 8321, Yunnan, China, August 2011.
[42]
R. Wetzel, M. Becker, J. Behlke et al., “Temperature behaviour of human serum albumin,” European Journal of Biochemistry, vol. 104, no. 2, pp. 469–478, 1980.
[43]
K. Takeda, A. Wada, K. Yamamoto, Y. Moriyama, and K. Aoki, “Conformational change of bovine serum albumin by heat treatment,” Journal of Protein Chemistry, vol. 8, no. 5, pp. 653–659, 1989.
[44]
C. N. Pace, S. D. Tevi？o, E. Prabhakaran, and J. M. Scholtz, “Protein structure, stability and solubility in water and other solvents,” Philosophical Transactions of the Royal Society B, vol. 39, no. 1448, pp. 1225–1235, 2004.
