Dextran permeation through poly(N-isopropylacrylamide) hydrogels

Area of Science:

• Materials Science
• Chemical Engineering
• Polymer Science

Background:

• Thermally reversible hydrogels are advanced materials with tunable properties.
• Understanding macromolecule transport is crucial for hydrogel applications in drug delivery and separation.

Purpose of the Study:

• To investigate the permeation of macromolecules through thermally reversible hydrogels.
• To develop and validate a permeation model incorporating hydrogel structural parameters and solute-molecule interactions.

Main Methods:

• Formulation of a permeation model considering hydrogel porosity, tortuosity, geometric restraints, and solute-pore wall friction.
• Experimental investigation of fluoroescein-labeled dextran fraction permeation through hydrogels.
• Estimation of hydrogel tortuosity and average pore size using the developed model.

Main Results:

• The developed permeation model effectively describes macromolecule transport through hydrogels.
• Accurate estimation of tortuosity and average pore size for poly(N-isopropylacrylamide) and poly(N-isopropylacrylamide-co-vinyl-terminated dimethylsiloxane) hydrogels.
• Model predictions showed good agreement with experimental permeation data for dextran molecules up to 43.5 A radius.

Conclusions:

• The study provides a robust model for predicting macromolecule permeation in hydrogels.
• The model successfully characterizes the transport properties of poly(N-isopropylacrylamide)-based hydrogels.
• This research contributes to the design and application of hydrogels in separation and delivery systems.