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Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
Smart zwitterionic membranes with on/off behavior for protein transport
Yanlei Su1, Lili Zheng, Chao Li
1Key Laboratory for Green Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China. suyanlei@tju.edu.cn
The Journal of Physical Chemistry. B
|September 5, 2008
Summary
Smart poly(acrylonitrile) (PAN)-based zwitterionic membranes exhibit electrolyte-sensitive properties, altering hydrophilicity and reducing protein adsorption. These reversible membranes can controllably switch protein transport channels based on salt concentrations.
Area of Science:
- Materials Science
- Polymer Chemistry
- Membrane Technology
Background:
- Poly(acrylonitrile) (PAN) is a versatile polymer used in membrane fabrication.
- Zwitterionic polymers offer unique properties like tunable hydrophilicity and reduced biofouling.
- Smart membranes respond to external stimuli, enabling dynamic control over transport processes.
Purpose of the Study:
- To develop and characterize novel PAN-based zwitterionic membranes with electrolyte-sensitive properties.
- To investigate the influence of electrolyte concentration on membrane hydrophilicity and protein adsorption.
- To explore the potential of these membranes for controlled protein transport.
Main Methods:
- Synthesis of PAN-based zwitterionic membranes incorporating poly(N,N-dimethyl-N-methacryloxyethyl-N-(3-sulfopropyl) copolymer.
- Fourier-transform infrared (FTIR) spectroscopy to analyze molecular changes in response to electrolytes.
- Protein adsorption and transport studies under varying sodium chloride (NaCl) concentrations.
Main Results:
- The zwitterionic membranes demonstrated increased hydrophilicity and significantly decreased protein adsorption upon exposure to environmental stimuli.
- FTIR analysis revealed enhanced dissociation and hydration of zwitterionic sulfobetaine dipoles at higher electrolyte concentrations.
- The membranes exhibited reversible, electrolyte-sensitive switching of protein transport channels, enabling an 'on/off' behavior.
Conclusions:
- PAN-based zwitterionic membranes function as electrolyte-sensitive smart materials.
- These membranes offer tunable control over protein transport by modulating NaCl concentrations.
- The reversible switching mechanism holds promise for advanced separation and purification applications.
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