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Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone
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Cholate Conjugated Polymeric Amphiphiles as Efficient Artificial Ionophores.
Subhasish Sahoo1, Jawad Ur Rehman2,3, Muhammad Raza Shah2
1Polymer Research Centre and Centre for Advanced Functional Materials, Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, West Bengal 741246, India.
ACS Applied Polymer Materials
|April 12, 2021
Summary
New amphiphilic copolymers with cholate groups effectively create pores in liposomes. This allows leakage of ions and molecules, with activity increasing with cholate content.
Area of Science:
- Polymer Chemistry
- Biomaterials Science
- Membrane Biophysics
Background:
- Amphiphilic copolymers are crucial for drug delivery and biomaterials.
- Cholic acid derivatives offer unique hydrophobic properties for material design.
- Liposomes are versatile nanocarriers with potential for targeted delivery.
Purpose of the Study:
- To synthesize and characterize novel amphiphilic copolymers incorporating cholate pendants.
- To investigate the ionophoric activity and membrane pore-forming capabilities of these copolymers.
- To correlate copolymer structure, specifically cholate content, with biological activity.
Main Methods:
- Copolymerization of 2-(methacryloxy)-ethyl cholate (MAECA) with polyethylene glycol methyl ether methacrylate (PEGMA).
- Varying the MAECA content from 0% to 35% in the synthesized copolymers.
- Assessing copolymer partitioning within liposomes and their effect on membrane permeability.
Main Results:
- Successful synthesis of amphiphilic copolymers with tunable cholate content.
- Copolymers demonstrated significant ionophoric activity, forming large pores in liposomal membranes.
- Enhanced leakage of small inorganic ions (H+, Na+) and large polar molecules (calcein) was observed.
- Ionophoric activity directly correlated with the increasing fraction of cholate moieties in the copolymers.
Conclusions:
- Amphiphilic copolymers with cholate pendants exhibit potent membrane-disrupting and ionophoric properties.
- The cholate content is a critical factor determining the efficacy of pore formation and substance leakage.
- These copolymers show promise as functional biomaterials for applications requiring membrane interaction.
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