A Thermometric Investigation of the Reaction between Proteins and 12-Phosphotungstic Acid

  • P. W. Carr
  • E. B. Smith
  • S. R. Betso
  • R. H. Callicott


Proteins in acid solution may be precipitated by the addition of a wide variety of anions including perchlorate, trifluoroacetate and tungstate(l). We have recently developed (2) a thermometric titration procedure for total serum protein based on their quantitative precipitation by 12-phosphotungstic acid (H3PW12O40). End point precision was~0 .5% when the total protein concentration was in the range of 1–10 g/l. Outside this range the precision deteriorates and the stoichiometry is not constant. At low protein concentration the reaction kinetics are too slow thereby inducing a positive error(3); while at high protein concentration the titration curve becomes quite nonlinear due to rather dramatic changes in the sample viscosity and concomitant changes in the rate of heat generation due to stirring (2).


Titration Curve Basic Amino Acid Total Serum Protein Bovine Albumin High Protein Concentration 
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  1. 1.
    R. J. Henry, Clinical Chemistry; Principles and Techniques, Harper and Row, New York, p. 163 (1964).Google Scholar
  2. 2.
    E. B. Smith and P. W. Carr, Anal. Chem., 45, 1688 (1973).CrossRefGoogle Scholar
  3. 3.
    P. W. Carr and J. Jordan, Anal. Chem., 45, 634 (1973).CrossRefGoogle Scholar
  4. 4.
    G. Scatchard, Y. V. Wu and A. L. Shen, J. Amer. Chem. Soc., 81 , 6104 (1959).CrossRefGoogle Scholar
  5. 5.
    G. Scatchard and W. T. Yap, J. Amer. Chem. Soc, 86, 3434 (1964).CrossRefGoogle Scholar
  6. 6.
    E. B. Smith, C.S. Barnesand P. W. Carr, Anal. Chem., 44, 1663 (1972).CrossRefGoogle Scholar
  7. 7.
    J.J. Christensen, R. M. Izatt and L. D. Hansen, Rev. Sci. Instrum., 36, 779 (1965).CrossRefGoogle Scholar
  8. 8.
    D. Rosenthall, G. L. Jones and R. Megargle, Anal. Chim. Acta., 53, 141 (1971).CrossRefGoogle Scholar
  9. 9.
    G. Schwartzenback, G. Geier and J. S. Sittler, Helv. Chim. Acta., 45, 2601 (1962).CrossRefGoogle Scholar
  10. 10.
    N. D. Jesperson and J. Jordan, Anal. Letters, 3, 323 (1970).CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1974

Authors and Affiliations

  • P. W. Carr
    • 1
  • E. B. Smith
    • 1
  • S. R. Betso
    • 1
  • R. H. Callicott
    • 1
  1. 1.Department of ChemistryUniversity of GeorgiaAthensUSA

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