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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
A dynamical theory of nucleation for colloids and macromolecules
1Center for Nonlinear Phenomena and Complex Systems, Code Postal 231, Université Libre de Bruxelles, Blvd. du Triomphe, 1050 Brussels, Belgium. jlutsko@ulb.ac.be
The Journal of Chemical Physics
|January 28, 2012
Summary
A new theory explains colloid and macromolecule nucleation using fluctuating hydrodynamics. It reveals a two-step protein nucleation mechanism, advancing classical nucleation theory.
Area of Science:
- Physical Chemistry
- Colloid Science
- Biophysics
Background:
- Classical nucleation theory often relies on equilibrium assumptions.
- Understanding nucleation pathways is crucial for phase transitions in solutions.
- Fluctuating hydrodynamics offers a dynamic framework for microscopic processes.
Purpose of the Study:
- To formulate a general theory of nucleation for colloids and macromolecules.
- To develop a formalism for determining nucleation pathways.
- To extend and justify existing nucleation theories.
Main Methods:
- Formulation of a general theory within fluctuating hydrodynamics.
- Development of stochastic differential equations for order parameter evolution.
- Application to globular protein transitions.
Main Results:
- A formalism for nucleation pathway determination is established.
- Conditions for recovering classical nucleation theory are identified.
- A novel two-step nucleation mechanism in globular proteins is revealed.
Conclusions:
- The theory provides a dynamic justification for equilibrium nucleation approaches.
- The identified two-step mechanism involves density fluctuations preceding nucleation.
- This work advances the understanding of nucleation in complex solutions.
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