Metal cation responsive anionic microgels: behaviour towards biologically relevant divalent and trivalent ions.
Vittoria Chimisso1, Simona Conti1, Phally Kong1
1Department of Chemistry, University of Basel, Mattenstrasse 24/a, 4002, Basel, Switzerland. wolfgang.meier@unibas.ch.
Soft Matter
|November 21, 2020
Summary
Anionic microgels can bind and release divalent cations, including Mg2+, Sr2+, Cu2+, and Fe3+. These biocompatible chelating agents show potential for treating iron overaccumulation in the digestive tract.
Area of Science:
- Polymer Chemistry
- Materials Science
- Biotechnology
Background:
- Anionic microgels offer tunable properties for ion binding.
- Metal ion interactions with charged polymer networks are crucial for responsive materials.
Purpose of the Study:
- To synthesize and characterize anionic poly(vinylcaprolactam-co-itaconicacid-co-dimethylitaconate) microgels.
- To investigate the microgels' responsiveness to various cations (Mg2+, Sr2+, Cu2+, Fe3+).
- To evaluate the potential of these microgels as biocompatible chelating agents, particularly for iron overload.
Main Methods:
- Dispersion polymerization for microgel synthesis.
- Dynamic Light Scattering (DLS) to measure microgel size changes in response to ions.
- Ion chromatography to quantify bound and released metal ions.
- Protonation studies to demonstrate ion release mechanisms.
Main Results:
- Synthesized anionic microgels demonstrated cation-induced crosslinking and size reduction.
- Microgels showed reversible binding and release of divalent cations over multiple cycles.
- Selective entrapment of Fe3+ over divalent cations was observed.
- Ion chromatography confirmed quantitative binding and release of Mg2+, Sr2+, Cu2+, and Fe3+.
Conclusions:
- The synthesized microgels exhibit reversible cation-binding capabilities, functioning effectively over multiple cycles.
- The selective Fe3+ entrapment highlights their potential application in managing iron overload conditions.
- These biocompatible microgels show promise as chelating agents for therapeutic applications in the digestive tract.
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