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An effective long-range attraction between protein molecules in solutions studied by small angle neutron scattering

Yun Liu·Emiliano Fratini·Piero Baglioni·Wei-Ren Chen·Sow-Hsin Chen
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Abstract

Small angle neutron scattering intensity distributions taken from cytochrome C and lysozyme protein solutions show a rising intensity at very small wave vector, Q, which can be interpreted in terms of the presence of a weak long-range attraction between protein molecules. This interaction has a range several times that of the diameter of the protein molecule, much greater than the range of the screened electrostatic repulsion. We show evidence that this long-range attraction is closely related to the type of anion present and ion concentration in the solution.

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Yun Liu, Emiliano Fratini, Piero Baglioni, Wei-Ren Chen, Sow-Hsin Chen. 2005-08-05. An effective long-range attraction between protein molecules in solutions studied by small angle neutron scattering. https://doi.org/10.1103/physrevlett.95.118102

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