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Diffuse Interface Methods for Modeling Drug-Eluting Stent Coatings

  • Medical Stents: State of the Art and Future Directions
  • Published:
Annals of Biomedical Engineering Aims and scope Submit manuscript

Abstract

An overview of diffuse interface models specific to drug-eluting stent coatings is presented. Microscale heterogeneities, both in the coating and use environment, dictate the performance of these coatings. Using diffuse interface methods, these heterogeneities can be explicitly incorporated into the model equations with relative ease. This enables one to predict the complex microstructures that evolve during coating fabrication and subsequent impact on drug release. Examples are provided that illustrate the wide range of phenomena that can be addressed with diffuse interface models including: crystallization, constrained phase separation, hydrolytic degradation, and heterogeneous binding. Challenges associated with the lack of material property data and numerical solution of the model equations are also highlighted. Finally, in light of these potential drawbacks, the potential to utilize diffuse interface models to help guide product and process development is discussed.

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Conflict of interest

No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript.

Disclaimers

The mention of commercial products, their source, or their use in connection with the material reported herein is not to be construed as either an actual or implied endorsement of the US Food and Drug Administration. Certain commercial equipment, instruments, or materials are identified in this paper in order to specify the experimental procedure adequately. Such identification is not intended to imply recommendation or endorsement by the National Institute of Standards and Technology, nor is it intended to imply that the materials or equipment identified are necessarily the best available for the purpose.

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Authors and Affiliations

  1. Food and Drug Administration, Silver Spring, MD, 20993, USA

    David M. Saylor & Christopher Forrey

  2. University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, USA

    Chang-Soo Kim

  3. National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA

    James A. Warren

Authors
  1. David M. Saylor
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  2. Christopher Forrey
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  3. Chang-Soo Kim
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  4. James A. Warren
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Correspondence to David M. Saylor.

Additional information

Communicated by Associate Editor Sean McGinty oversaw the review of this article.

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Saylor, D.M., Forrey, C., Kim, CS. et al. Diffuse Interface Methods for Modeling Drug-Eluting Stent Coatings. Ann Biomed Eng 44, 548–559 (2016). https://doi.org/10.1007/s10439-015-1375-7

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  • DOI: https://doi.org/10.1007/s10439-015-1375-7

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