Related Experiment Video
Updated: Jul 12, 2026
18:57
Models and Methods to Evaluate Transport of Drug Delivery Systems Across Cellular Barriers
Published on: October 17, 2013
Testing Bound-State Diffusion as a Model for Mucosal Transport of Nanoparticles.
Damien M Trujeque1, Ameya G Prabhune2, Nuris Figueroa-Morales2
1Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, Aurora, Colorado 80045, United States.
ACS Applied Bio Materials
|July 9, 2026
Summary
New nanoparticles designed with hyaluronic acid (HA) demonstrate enhanced mucus penetration. This bound-state diffusion approach allows therapeutic delivery through mucosal barriers, overcoming previous limitations.
Area of Science:
- Biomedical Engineering
- Materials Science
- Drug Delivery
Background:
- Mucus presents a significant barrier to therapeutic delivery at epithelial surfaces.
- Conventional nanoparticles face challenges of either being washed away or having limited mobility within mucus.
Purpose of the Study:
- To test the bound-state diffusion hypothesis for enhanced mucus penetration of nanoparticles.
- To design nanoparticles that can overcome mucus barriers for effective therapeutic delivery.
Main Methods:
- Utilized bacteriophage-based nanoparticles decorated with hyaluronic acid (HA) polymers of varying lengths (10 and 50 kDa).
- Investigated nanoparticle mobility within mucus using the bound-state diffusion framework.
- Co-decorated nanoparticles with HA and MVASI (an antibody) to assess biological activity retention.
Main Results:
- Nanoparticles with long HA polymers exhibited significant mobility within mucus, despite HA's known mucus-binding properties.
- The observed mobility aligns with the bound-state diffusion hypothesis, enabling motion while bound.
- Co-decorated nanoparticles maintained both muco-diffusive properties and the biological activity of the MVASI antibody.
Conclusions:
- Bound-state diffusion is a feasible strategy for designing nanoparticles capable of penetrating mucosal barriers.
- This approach facilitates the delivery of biologics through mucus, overcoming limitations of previous nanoparticle designs.
- The study demonstrates the potential for improved therapeutic delivery across epithelial surfaces.
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