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The Determination of Protonation Constants of Some Amino Acids and Their Esters by Potentiometry in Different Media

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In this study, stoichiometric protonation constants of L-tyrosine, L-cysteine, L-tryptophane, L-lysine, and L-histidine, and their methyl and ethyl esters in water and ethanol–water mixtures of 30, 50, and 70% ethanol (v/v), were determined potentiometrically using a combined pH electrode system calibrated as the concentration of hydrogen ion. Titrations were performed at 25C and the ionic strength of the medium was maintained at 0.10 mol⋅L−1 using sodium chloride. Protonation constants were calculated by using the BEST computer program. The effect of solvent composition on the protonation constants is discussed. The log10 K2 values of esters generally decreased with increasing ethanol content. However, the log10 K1 values of the esters of L-tyrosine, L-cysteine, and L-tryptophane were found to increase with increasing ethanol content in contrast those of L-lysine and L-histidine esters.

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References

  1. S. Fiol, I. Brandariz, and M. Sasrte de Vicente, The Ionization Constants of Alanine in NaCl at 25 ∘C. Effect of the Ionic Strength Based on Three Models, Talanta 42, 797–801 (1995).

    Article  CAS  Google Scholar 

  2. I. J. Partanen, Calculation of the First and Second Stoichiometric Dissociation Constants of Glycine in Aqueous Sodium Chloride Solutions at 298.15 K, Ber. Bunsenges. Phys. Chem. 102, 855–864 (1998).

    CAS  Google Scholar 

  3. D. L. Hughes, J. J. Bergan, and E. J. J. Grabowski, Amino Acid Chemistry in Dipolar Aprotic Solvents; Dissociation Constants and Ambident Reactivity, J. Org. Chem. 51, 2579–2585 (1986).

    Article  CAS  Google Scholar 

  4. J. Crosby, R. Stone, and G. E. Lienhard, Mechanisms of Thiamine-catalyzed Reactions. Decarboxylation of 2-(1-carboxy-1-hydroxyethyl)-3,4-dimethylthiazolium Chloride, J. Am. Chem. Soc. 92, 2891–2900 (1970).

    CAS  Google Scholar 

  5. N. Nishi, S. Takahashi, M. Matsumoto, A. Tanaka, K. Muraya, T. Taramuku, and T. Yamaguchi, Hydrogen-bonded Cluster Formation and Hydrophobic Solute Association in Aqueous Solutions of Ethanol, J. Phys. Chem. 99, 462–468 (1995).

    Article  CAS  Google Scholar 

  6. H. Rossotti, The Study of Ionic Equilibria (Longman, London, 1978).

    Google Scholar 

  7. A. E. Martell and M. Calvin, Chemistry of the Metal Chelate Compounds (Prentice-Hall Inc., New York, 1952).

    Google Scholar 

  8. F. C. Rossotti and H. Rossotti, The Determination of Stability Constant (McGraw–Hill Inc., New York, 1961).

  9. R. G. Bates, Determination of pH, Theory and Practice (John Wiley and Sons, New York, 1973).

    Google Scholar 

  10. D. D. Perrin and W. Armerego, Purification of Laboratory Chemicals (Pergamon Press, Oxford, 1966).

    Google Scholar 

  11. G. Gran, Determination of the Equivalent Point in Potentiometric Titrations, Part I. Acta Chem. Scand. 4, 559–577 (1950).

    CAS  Google Scholar 

  12. G. Gran, Determination of the Equivalent Point in Potentiometric Titrations, Part II, Analyst 77, 661–671 (1952).

    Article  CAS  Google Scholar 

  13. A. E. Martell and R. J. Motekaitis, The Determination and Use of Stability Constants (VCH, Weinheim, 1988).

    Google Scholar 

  14. M. Meloun, J. Havel, and H. Högfelt, Computation of Solution Equilibria (Wiley, New York, 1988).

    Google Scholar 

  15. E. P. Serjeant, Potentiometry and Potentiometric Titrations (Wiley, NY, 1984).

    Google Scholar 

  16. E. M. Woolley, D. G. Hukot, and L. G. Hepler, Ionization Constants for Water in Aqueous Organic Mixtures, J. Phys. Chem. 74, 3908–3913 (1970).

    Google Scholar 

  17. S. Rondinini, T. Mussini, and P. R. Mussini, Autoprotolysis Constants in Nonaqueous Solvents and Aqueous Organic-solvent Mixtures, Pure Appl. Chem. 59, 1693–1702 (1987).

    CAS  Google Scholar 

  18. R. J. Motekaitis and A. E. Martell, Program PKAS: A Novel Algorithm or the Computation of Successive Protonation Constants, Can. J. Chem. 60, 1681–1689 (1982).

    Google Scholar 

  19. R. J. Motekaitis and A. E. Martell, Best—A New Program for Rigorous Calculation of Equilibrium Parameters of Complex Multi-component Systems, Can. J. Chem. 60, 2403–2409 (1982).

    CAS  Google Scholar 

  20. R. F. Jameson and M. F. Wilson, Thermodynamics of the Interactions of Catechol with Transition Metals. Part I. Free Energy, Enthalpy, and Entropy Changes for the Ionisation of Catechol at 25,∘C. Comparison of the Temperature-coefficient Method with Direct Calorimetry, J. Chem. Soc. Dalton Trans. 2507–2610 (1972).

  21. E. Kiliç and N. Arslan, Determination of Autoprotolysis Constants of Water-Organic Solvent Mixtures by Potentiometry. Microchim Acta, 151, 89–92 (2005).

    Article  Google Scholar 

  22. H. A. Azab, A. M. El-Nady, S. A. El-Shatoury, and A. Hassan, Potentiometric Determination of the Dissociation Constants of l-Histidine, Proline and Tryptophane in Various Hydroorganic Media, Talanta, 41, 1255–1259 (1994).

    Article  Google Scholar 

  23. A. Dogan, F. Köseoglu, and E. Kiliç, Studies on the Macroscopic Protonation Constants of Some α-Amino Acids in Ethanol–Water Mixtures, Anal. Biochem. 309, 75–78 (2002).

    Article  CAS  Google Scholar 

  24. F. Apruzzese, E. Bottari, and M. R. Festa, Protonation Equilibria and Solubility of l-Cystine, Talanta 56, 459–469 (2002).

    Article  CAS  Google Scholar 

  25. B. Nowak and Z. Pawlak, Dissociation of Some Phenols in Acetone + Water Mixtures, J. Chem. Soc., Faraday Trans. 1 78, 2693–2700 (1982).

    Article  CAS  Google Scholar 

  26. A. A. Mohamed, F. M. Bakr, and A. K. Abd El-Fattah, Thermodynamic Studies on the Interaction Between Some Amino Acids with Some Rare Earth Metal Ions in Aqueous Solutions, Thermochim. Acta 405, 235–253 (2003).

    Article  CAS  Google Scholar 

  27. D. V. Jahagirdar, B. Arbad, T. K. Chondhekar, and S. U. Pankanti, Thermodynamics of Transfer of Amino-Acids from Water to Ethanol–Water Mixtures, Ind. J. Chem. 28A, 366–370 (1989).

    CAS  Google Scholar 

  28. A. K. Chattopadhyay and S. C. Lahiri, Studies on the Solvation of Amino Acids in Ethanol and Water Mixtures, Electrochim. Acta27, 269–272 (1982).

    Article  CAS  Google Scholar 

  29. P. G. Daniele, P. Amico, and G. Ostacoli, Binary and Ternary Cu(II) Complexes with Malonic Acid and Glycine in Water and Water-1-propanol Mixtures, J. Inorg. Nucl. Chem. 43, 2183–2187 (1981).

    Article  CAS  Google Scholar 

  30. F. Köseoglu, E. Kiliç, and A. Dogan, Studies on the Protonation Constants and Solvation of α-Amino Acids in Dioxan-water Mixtures, Anal. Biochem. 277, 243–246 (2000).

    Google Scholar 

  31. A. Dogan and E. Kiliç, Potentiometric Studies on the Protonation Constants and Solvation of Some α-Amino Acid Benzyl- and t-Butyl-esters in Ethanol–Water Mixtures, Turk. J. Chem. 29, 41–47 (2005).

    CAS  Google Scholar 

  32. A. Dogan, F. Köseoglu, and E. Kiliç, The Stability Constants of Copper(II) Complexes with Some α-Amino Acids in Dioxan–Water Mixtures, Anal. Biochem. 295, 237–239 (2001).

    Article  CAS  Google Scholar 

  33. J. T. Edsall and M. H. Blanchard, The Activity Ratio of Zwitterions and Uncharged Molecules in Ampholyte Solutions. The Dissociation Constants of Amino Acid Esters, J. Am. Chem. Soc. 55, 2337–2353 (1937).

    Google Scholar 

  34. C. De Stefano, C. Foti, A. Gianguzza, and S. Sammartano, Chemical Speciation of Amino-Acids in Electrolyte Solutions Containing Major Components of Natural Fluids, Chem. Speciation Bioavailability 7, 1–8 (1995)

    CAS  Google Scholar 

  35. A. E. Martel and R. M. Smith, Critical Stability Constants, Vol. 1, (Plenum Press, New York, 1989).

  36. E. Bottari and M. R. Festa, On the Behaviour of Cysteine as Ligand of Cadmium(II), Talanta 4, 1705–1718 (1997).

    Google Scholar 

  37. C. L. Sharma and S. S. Narvi, Thermochemistry for the Formation of Cysteinate Complex of Rhodium(III), Thermochim. Acta 90, 1–8 (1985).

    Article  CAS  Google Scholar 

  38. R. H. Garrett and C. M. Grisham, Biochemistry (Harcourt Brace College Publishers, USA, 1999).

    Google Scholar 

  39. S. H. Hilal, Y. Shabrawy, L. A. Carreira, and S. W. Karickhoff, Estimation of Microscopic, Zwitterionic Ionization Constants, Isoelectric Point and Molecular Speciation of Organic Compounds, Talanta 50, 827–840 (1999).

    Article  CAS  Google Scholar 

  40. M. S. K. Niazi and J. Mollin, Dissociation Constants of Some Amino Acids and Prydinecarboxylic Acids in Ethanol–Water Mixtures, Bull. Chem. Soc. 60, 2605–2610 (1987).

    CAS  Google Scholar 

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Correspondence to Esma Kilıç.

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Canel, E., Gültepe, A., Doğan, A. et al. The Determination of Protonation Constants of Some Amino Acids and Their Esters by Potentiometry in Different Media. J Solution Chem 35, 5–19 (2006). https://doi.org/10.1007/s10953-006-8934-3

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  • DOI: https://doi.org/10.1007/s10953-006-8934-3

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