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Updated: Jun 23, 2026
06:10
Encapsulated Cell Technology for the Delivery of Biologics to the Mouse Eye
Published on: March 30, 2020
An injectable drug delivery platform for sustained combination therapy
M Douglas Baumann1, Catherine E Kang, Jason C Stanwick
1Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON, Canada. douglas.baumann@utoronto.ca
Summary
We developed novel hyaluronan (HA) and methyl cellulose (MC) hydrogels for sustained drug delivery in spinal cord injury repair. These injectable hydrogels offer tunable, long-term release of neuroprotective and neuroregenerative agents.
Area of Science:
- Biomaterials Science
- Regenerative Medicine
- Drug Delivery Systems
Background:
- Spinal cord injury (SCI) repair requires strategies for sustained delivery of therapeutic agents.
- Existing hydrogel systems often lack tunable and long-term drug release profiles.
- Developing advanced biomaterials is crucial for effective SCI treatment.
Purpose of the Study:
- To engineer composite hydrogels of hyaluronan (HA) and methyl cellulose (MC) for controlled drug delivery.
- To achieve diverse drug release profiles for spinal cord injury repair applications.
- To evaluate the stability, injectability, and release characteristics of the developed hydrogels.
Main Methods:
- Fabrication of physical hydrogel blends of hyaluronan (HA) and methyl cellulose (MC).
- Incorporation of poly(lactide-co-glycolide) (PLGA) particles for controlled drug release.
- Assessment of drug release kinetics for various molecules (NBQX, FGF-2, dbcAMP, EGF, proteins).
- Evaluation of hydrogel stability, swelling, and injectability.
Main Results:
- Composite HA-MC hydrogels demonstrated significantly enhanced stability compared to HA-MC alone.
- Achieved tunable drug release from 1 to 28 days using diffusion and particle-based mechanisms.
- Successfully delivered neuroprotective (NBQX, FGF-2) and neuroregenerative (dbcAMP, EGF) agents.
- Model proteins (alpha-chymotrypsin, IgG) were released over 28 days, indicating potential for neurotrophins.
- Hydrogels exhibited minimal swelling and were injectable with high particle loads (up to 15 wt.%).
Conclusions:
- The developed HA-MC composite hydrogels offer a promising platform for sustained and controlled delivery of therapeutics for spinal cord injury repair.
- The combination of hydrogel matrix and PLGA particles allows for versatile release profiles.
- These injectable and stable hydrogels represent a significant advancement in biomaterial-based SCI treatment strategies.
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