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Models and Methods to Evaluate Transport of Drug Delivery Systems Across Cellular Barriers
Published on: October 17, 2013
Elaborations on the Higuchi model for drug delivery.
1Department of Chemical Engineering, University of Texas at Austin, Austin, TX 78712, USA. drp@che.utexas.edu
International Journal of Pharmaceutics
|November 2, 2010
Summary
The Higuchi model, celebrating 50 years, remains crucial for controlled drug delivery from matrix devices. This review covers its core principles, assumptions, and key extensions for drug release applications.
Area of Science:
- Pharmacology
- Materials Science
- Chemical Engineering
Background:
- The Higuchi model is fundamental for understanding drug release from matrix systems.
- It is particularly relevant when drug loading exceeds matrix solubility.
- The model has significantly contributed to the controlled drug delivery industry over 50 years.
Purpose of the Study:
- To review the conceptual and mathematical foundations of the Higuchi model.
- To discuss the implications of the model's inherent assumptions.
- To summarize important extensions of the Higuchi model.
Main Methods:
- Conceptual review of the Higuchi model's theoretical basis.
- Mathematical analysis of the model's equations and assumptions.
- Summary and discussion of selected model extensions.
Main Results:
- The Higuchi model provides a robust framework for drug release kinetics.
- Key assumptions and their consequences on drug release were analyzed.
- Extensions addressing external mass transfer and drug loading variations were highlighted.
Conclusions:
- The Higuchi model's enduring relevance in drug delivery is confirmed.
- Understanding model assumptions is critical for accurate predictions.
- Model extensions enhance its applicability to complex drug delivery systems.
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