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15:33
Microwave-assisted Functionalization of Polyethylene glycol and On-resin Peptides for Use in Chain Polymerizations and Hydrogel Formation
Published on: October 29, 2013
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Particle transport through hydrogels is charge asymmetric
Xiaolu Zhang1, Johann Hansing2, Roland R Netz2
1Department of Chemistry, University of Kentucky, Lexington, Kentucky.
Biophysical Journal
|February 5, 2015
Summary
Electrostatic interactions significantly impact how charged molecules move through biological polymer networks. Diffusion is slowed more by attraction than repulsion, affecting the network
Area of Science:
- Biophysics
- Materials Science
- Physical Chemistry
Background:
- Biological polymer networks like mucus and extracellular matrix are crucial for molecular and nanoparticle exchange in the human body.
- These hydrogel environments regulate diffusion through complex particle-network interactions.
Purpose of the Study:
- To investigate the influence of electrostatics on the diffusion mechanisms of charged probe molecules within model polymer networks.
- To understand how charged hydrogels filter molecules and nanoparticles.
Main Methods:
- Utilized fluorescence correlation spectroscopy to measure translational diffusion coefficients of charged probe molecules.
- Employed Brownian dynamics simulations to model particle-network interactions and key parameters.
Main Results:
- Demonstrated highly asymmetric particle transport in charged hydrogels, with attraction impeding diffusion more than repulsion.
- Showcased the sensitivity of gel filtering capabilities to solution ionic strength.
- Simulation results quantitatively agreed with experimental findings.
Conclusions:
- The charge asymmetry in particle transport arises from particles sticking to oppositely charged polymer network vertices.
- Electrostatic interactions are a critical factor in controlling transport and filtering in biological hydrogels.
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