A modified experimental set-up for sedimentation equilibrium experiments with gels. Part I: The instrumentation

  • H. Cölfen
  • W. Borchard
Conference paper
Part of the Progress in Colloid & Polymer Science book series (PROGCOLLOID, volume 94)


An experimental set-up for the determination of swelling pressure-concentration curves and thermodynamic and elastic properties of gels by means of analytical ultracentrifugation is presented. The instrumentation described allows an accurate measurement of up to 70 samples simultaneously in an equilibrium experiment which lasts about 2 days if the 10-hole multichannel centerpieces described in part 2 of this trilogy are used. The number of samples is enough to characterize one cofmeplete gel/solvent system by important thermodynamic, structural and elastic parameters in the experimentally accessible range. It is of great advantage that all samples are measured under exactly the same conditions. Thisd is not possible by means of classical methods which all yield only one swelling pressure corresponding to one concentration. The evaluation process of the Schlieren patterns is fully automated to ensure a user-friendly process.

Key words

Gels analytical ultracentrifugation sedimentation equilibrium swelling pressure computerized Schlieren pattern evaluation 


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  1. 1.
    Tanaka T (1987) In: Mark, Bikales, Overberger, Menges (eds) Encyclopedia of Polymer Science and Engineering. Vol 7, John Wiley & Sons, p 514Google Scholar
  2. 2.
    Cölfen H (1991) Diplomarbeit, DuisburgGoogle Scholar
  3. 3.
    Holtus G, Cölfen H, Borchard W (1991) Progr Colloid Polym Sci 86:92CrossRefGoogle Scholar
  4. 4.
    Morchard W, Cölfen H (1992) Makromol Chem, Macromol Symp 61:143Google Scholar
  5. 5.
    Hinsken H (1992) Diplomarbeit, DuisburgGoogle Scholar
  6. 6.
    Hinsken H, Borchard W (1993) submittedGoogle Scholar
  7. 7.
    Cölfen H (1993) Dissertation, DuisburgGoogle Scholar
  8. 8.
    Holtus H (1990) Dissertation, DuisburgGoogle Scholar
  9. 9.
    Cölfen H, Borchard W (1991) Progr Colloid Polym Sci 86:102Google Scholar
  10. 10.
    Holtus G, Borchard W (1989) Colloid Polym Sci 267:1133CrossRefGoogle Scholar
  11. 11.
    Yphantis DA (1960) “Rapid determination of molecular weights of peptides and proteins” Ann N Y Acad Sci 88:586CrossRefGoogle Scholar
  12. 12.
    van Holde KE, Baldwin RL (1958) J Phys Chem 62:734CrossRefGoogle Scholar
  13. 13.
    Laue TM (1992) “Short Column Sedimentation Equilibrium Analysis for Rapid Characterization of Macromolecules in Solution” Beckman Instruments, Technical InformationGoogle Scholar
  14. 14.
    Cölfen H, Borchard W, “A modified experimental set-up for sedimentation equilibrium experiments with gels: Part II Technical developments” (submitted to Anal Biochem)Google Scholar
  15. 15.
    Cölfen H, Borchard W, ”A modified experimental set-up for sedimentation equilibrium experiments with gels: Part III Results” (in preparation)Google Scholar
  16. 16.
    Borchard W (1991) Progr Colloid Polym Sci 86:84Google Scholar
  17. 17.
    Borchard W (1993) this issueGoogle Scholar
  18. 18.
    Svedberg T, Pedersen KO (1940) Die Ultrazentrifuge. Steinkopff, DresdenGoogle Scholar
  19. 19.
    Johnson P (1971) J Photograph Sci 19:49Google Scholar
  20. 20.
    Johnson P (1970) Velocity and equilibrium aspects of the sedimentation of agar gels in Photographic Gelatin I, Academic Press, London: 13Google Scholar
  21. 21.
    Bloomfield VA (1976) Biopolymers 15:1243CrossRefGoogle Scholar
  22. 22.
    Cölfen H, Borchard W (1993) submitted to Makromol ChemGoogle Scholar
  23. 23.
    Paul CH, Yphantis DA (1972) Anal Biochem 48:588CrossRefGoogle Scholar
  24. 24.
    Ortlepp B, Panke D (1991) Progr Colloid Polym Sci 86:57Google Scholar
  25. 25.
    Mächtle W, Klodwig U (1989) Colloid Polym Sci 267:1117CrossRefGoogle Scholar
  26. 26.
    Laue TM (1992) “On-line Data Aquisition and Analysis from the Rayleigh Interferometer” in Harding SE et al (Ed) “Analytical Ultracentrifugation in Biochemistry and Polymer Science” Royal Society of Chemistry, Cambridge, England: 63Google Scholar
  27. 27.
    Laue TM, “Real time interferometry in the ultracentrifuge” (1993) SPIE Proceedings Vol 1895 “Ultrasensitive Laboratory Diagnostics” (in press)Google Scholar
  28. 28.
    Holtus G, Kiepen F, Schwark K, Borchard W (1990) Makromol Chem, Rapid Commun 11:177CrossRefGoogle Scholar

Copyright information

© Dr. Dietrich Steinkopff Verlag GmbH & Co. KG 1994

Authors and Affiliations

  • H. Cölfen
    • 1
  • W. Borchard
    • 1
  1. 1.Angewandte Physikalische ChemieUniversität-GH-DuisburgDuisburgFRG

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