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Published on: September 2, 2009
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Electromechanical convective drug delivery devices for overcoming diffusion barriers
Jihoon Park1, Ramy Ghanim1, Adwik Rahematpura2
1School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Summary
This review compares diffusive and convective drug delivery systems. Convection-enabling devices significantly improve drug bioavailability across physiological barriers, outperforming diffusion-based methods.
Area of Science:
- Biomedical Engineering
- Drug Delivery Systems
- Pharmacology
Background:
- Diffusion-based drug delivery systems (hydrogels, nanoparticles) improve targeting and extend drug profiles for diseases like cancer and diabetes.
- These systems struggle with low bioavailability (<0.01-1%) for macromolecules across challenging tissues (skin, tumors, blood-brain barrier, GI walls).
Purpose of the Study:
- To compare diffusive and convective drug delivery systems.
- To highlight engineering techniques for enhancing convective device efficacy.
- To provide examples of synergistic combinations of diffusive and convective transport.
Main Methods:
- Review of existing literature on diffusion-dependent and convection-enabling drug delivery.
- Comparative analysis of mass transport mechanisms (diffusion vs. convection).
- Examination of engineering strategies for convective drug delivery devices (ingestibles, wearables, implantables).
Main Results:
- Convective mass transfer, utilizing bulk fluid flow, enhances drug bioavailability by orders of magnitude.
- Robotic ingestibles, wearables, and implantables physically interact with tissue walls to enable convection.
- Synergies between diffusion and convection offer potential for improved therapeutic outcomes.
Conclusions:
- Convective drug delivery systems offer a significant advancement over diffusion-based methods for overcoming physiological barriers.
- Engineering innovative convective devices is crucial for improving drug bioavailability and patient health.
- Combining diffusive and convective strategies presents a promising future for advanced drug delivery.
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