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Updated: Aug 12, 2026

Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
Understanding salt or PEG induced attractive interactions to crystallize biological macromolecules
Annette Tardieu1, Françoise Bonneté, Stéphanie Finet
1LMCP, Case 115, 4 Place Jussieu, F75252 Paris Cedex 05, France. Annette.Tardieu@lmcp.jussieu.fr
Abstract:
Phase diagrams of biological macromolecules are governed by an appropriate combination of interaction potentials in solution. Repulsive regimes favor solubility, whereas the presence of attractive potentials may induce a variety of phase transitions, including the desired macromolecular crystallization. The forces at work may be analyzed with a combination of small angle X-ray scattering and of numerical treatments. From the results obtained with a variety of model systems, the respective advantages and drawbacks of using monovalent salts or PEGs as crystallizing agents are discussed.
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