Can PEI microgels become biocompatible upon betainization?

Area of Science:

• Materials Science
• Polymer Chemistry
• Biotechnology

Background:

• Polyethylene imine (PEI) microgels are synthesized via microemulsion polymerization.
• PEI microgels possess inherent antibacterial properties but also exhibit toxicity.
• Developing safer and functionalized PEI-based materials is of significant interest.

Purpose of the Study:

• To synthesize betainized PEI (b-PEI) microgels by modifying PEI microgels with 1,3-propane sultone.
• To investigate the structural, physical, and functional property changes in PEI microgels after betainization.
• To evaluate the dye adsorption capabilities and biocompatibility of the modified b-PEI microgels.

Main Methods:

• Microemulsion polymerization to prepare PEI microgels.
• Chemical modification of PEI microgels with 1,3-propane sultone to introduce zwitterionic groups.
• Characterization of microgel size, zeta potential, and dye adsorption capacity.
• Biocompatibility assessment using WST-1 assays and cytotoxicity, apoptosis, and necrosis tests.

Main Results:

• Betainization increased microgel size and imparted negative zeta potential at high pH.
• b-PEI microgels demonstrated significantly enhanced adsorption capacities for Methyl Orange (354±31 mg/g) and Methylene Blue (274±19 mg/g).
• Antibacterial activity against E. coli and S. aureus was diminished, while PEI microgels showed no cytotoxicity up to 400 μg/mL, indicating biocompatibility.

Conclusions:

• Betainization of PEI microgels successfully generated zwitterionic structures with altered properties.
• The modified b-PEI microgels show promise for dye removal applications.
• Betainization effectively mitigates the toxicity of PEI microgels, rendering them biocompatible for potential biomedical or environmental applications.