Skip to main content
SpringerLink
Log in

Electrochemical etching of micro-pores in medical grade cobalt–chromium alloy as reservoirs for drug eluting stents

  • Delivery Systems
  • Original Research
  • Published:
Journal of Materials Science: Materials in Medicine Aims and scope Submit manuscript

Abstract

Drug eluting stents (DES) have shown efficacy in reducing restenosis after angioplasty followed by application of a coronary stent. However, polymer matrices typically used for immobilizing drugs on the stent surface may cause irritation and have limited drug loading capacity. In contrast, drug loading into micro- or nanopores created within the stent material could avoid these problems. We present a technology based on electrochemically induced pitting corrosion to form pores in medical grade steel, followed by loading with rapamycin. This process is applied to pore formation and drug loading in coronary stents consisting of L605 medical steel. Sustained release of the drug over 28 days at rates comparable to established DES was demonstrated. This technology is capable of creating pores with well-defined pore size and filling of these pores by a drug employing a crystallization process thus completely avoiding polymer matrices to immobilize drugs. Electrochemically induced pitting corrosion provides a generic means to introduce micro-pores suitable as drug reservoirs into medical grade steel without the need for any further matrix material. Further research will expand these findings to other materials and types of implants that could benefit from the additional function of drug release and/or improved implant/tissue integration.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9

Similar content being viewed by others

References

  1. Bennett MR. In-stent stenosis: pathology and implications for the development of drug eluting stents. Heart. 2003;89(2):218–24.

    Article  Google Scholar 

  2. Tsujino I, et al. Drug delivery via nano-, micro and macroporous coronary stent surfaces. Expert Opin Drug Deliv. 2007;4(3):287–95.

    Article  Google Scholar 

  3. Cutlip D, Abbott JD. 2015. Drug-eluting compared to bare metal intracoronary stents. http://www.uptodate.com/contents/drug-eluting-compared-to-bare-metal-intracoronary-stents. Accessed 23 Mar 2015.

  4. Capodanno D, Dipasqua F, Tamburino C. Novel drug-eluting stents in the treatment of de novo coronary lesions. Vasc Health Risk Manag. 2011;7:103.

    Google Scholar 

  5. Ernst A, Bulum J. New generations of drug-eluting stents-a brief review. Eur Med J Interv Cardiol. 2014;1:100–6.

    Google Scholar 

  6. Ma X, Wu T, Robich MP. Drug-eluting stent coatings. Interv Cardiol. 2012;4(1):73–83.

    Article  Google Scholar 

  7. Shand JA, Menown IB. Drug-eluting stents: the next generation. Interv Cardiol. 2010;2(3):341–50.

    Article  Google Scholar 

  8. Abizaid A, Costa JR. New drug-eluting stents an overview on biodegradable and polymer-free next-generation stent systems. Circulation. 2010;3(4):384–93.

    Google Scholar 

  9. Aoki J. Complications of polymers on drug-eluting stents: looking toward polymer-free drug-eluting stents. Intern Med. 2015;54(6):549–50.

    Article  Google Scholar 

  10. Variola F, et al. Nanoscale surface modifications of medically relevant metals: state-of-the art and perspectives. Nanoscale. 2011;3(2):335–53.

    Article  Google Scholar 

  11. Preparation method of metal support surface micro blind hole drug-loaded layer. 2008, Google Patents.

  12. Poncin P, et al. Comparing and optimizing Co–Cr tubing for stent applications. In: Proceedings of the materials and processes for medical devices conference. 2004.

  13. Sul Y-T, Byon E, Wennerberg A. Surface characteristics of electrochemically oxidized implants and acid-etched implants: surface chemistry, morphology, pore configurations, oxide thickness, crystal structure, and roughness. Int J Oral Maxillofac Implant. 2007;23(4):631–40.

    Google Scholar 

  14. Schuessler A., et al. Manufacturing of stents: optimize the stent with new manufacturing technology. In: 5th European symposium of vascular biomaterials ESVB. 2007.

  15. Marcus P. Corrosion mechanisms in theory and practice. 3rd ed. Boca Raton: Taylor & Francis; 2011.

    Book  Google Scholar 

  16. Roberge P. Corrosion engineering: principles and practice. New York: McGraw-Hill Education; 2008.

    Google Scholar 

  17. McCafferty E. Introduction to corrosion science. New York: Springer; 2010.

    Book  Google Scholar 

  18. Pourbaix M. Atlas of electrochemical equilibria in aqueous solutions. Houston: National Association of Corrosion Engineers; 1974.

    Google Scholar 

  19. Galvele JR, 1—pitting corrosion. In: SJC editor. Treatise on materials science and technology. Elsevier; 1983. p. 1–57.

  20. Levy Y, Khan W, Farah S, Domb AJ. Surface crystallization of rapamycin on stents using a temperature induced process. Langmuir. 2012;28(15):6207–10. doi:10.1021/la300364y.

    Article  Google Scholar 

  21. Strehblow HH. Breakdown of passivity and localized corrosion: theoretical concepts and fundamental experimental results. Mater Corros. 1984;35(10):437–48.

    Article  Google Scholar 

  22. Dash S, et al. Kinetic modeling on drug release from controlled drug delivery systems. Acta Pol Pharm. 2010;67(3):217–23.

    Google Scholar 

  23. Van den Mooter G. The use of amorphous solid dispersions: a formulation strategy to overcome poor solubility and dissolution rate. Drug Discov Today. 2012;9(2):e79–85.

    Article  Google Scholar 

  24. Ernst A, Bulum J. New generations of drug-eluting stents—a brief review. EMJ Int Cardiol. 2014;1:100-6.

    Google Scholar 

Download references

Acknowledgments

This research was funded by the German Ministry for Education and Research through Grant No. 13N11221. Stents were a generous gift of Qualimed Innovative Medizinprodukte GmbH, Winsen, Germany.

Author information

Authors and Affiliations

  1. NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany

    Kai Fuchsberger, Karoline Binder, Claus Burkhardt, Christian Freudigmann, Markus Herrmann & Martin Stelzle

Authors
  1. Kai Fuchsberger
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Karoline Binder
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Claus Burkhardt
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Christian Freudigmann
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Markus Herrmann
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Martin Stelzle
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Martin Stelzle.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (DOCX 328 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Fuchsberger, K., Binder, K., Burkhardt, C. et al. Electrochemical etching of micro-pores in medical grade cobalt–chromium alloy as reservoirs for drug eluting stents. J Mater Sci: Mater Med 27, 47 (2016). https://doi.org/10.1007/s10856-015-5660-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s10856-015-5660-7

Keywords

Search

Navigation