Characterization of Therapeutic Coatings on Medical Devices
Therapeutic coatings on medical devices such as catheters, guide wires, and stents improve biocompatibility by favorably altering the chemical nature of the device/tissue or device/blood interface. Such coatings often minimize tissue damage (reduce friction), decrease chances for blood clot formation (prevent platelet adsorption), and improve the healing response (deliver drugs). Confocal Raman microscopy provides valuable information about biomedical coatings by, for example, facilitating the measurement of the thickness and swelling of frictionreducing hydrogel coatings on catheters and by determining the distribution of drug within a polymer-based drug-eluting coatings on stents. This chapter explores the application of Raman microscopy to the imaging of thin coatings of cross-linked poly(vinyl pyrrolidone) gels, parylene films, mixtures of dexamethasone with various polymethacrylates, and mixtures of rapamycin with hydrolysable (biodegradable) poly(lactide-co-glycolide) polymers. Raman microscopy measures the thickness and swelling of coatings, reveals the degree of mixing of drug and polymer, senses the hydrolysis of biodegradable polymers, and determines the polymorphic forms of drug present within thin therapeutic coatings on medical devices.
KeywordsAlkyl Chain Length Vinyl Pyrrolidone Raman Microscopy Butyl Methacrylate Raman Image
Unable to display preview. Download preview PDF.
- 1.B. Ratner, A. Hoffman, F. Schoen, J. Lemons, Biomaterials Science: An Introduction to Materials in Medicine, 2nd edn. (Academic, San Diego, London, 2004)Google Scholar
- 4.P. Serruys, A. Gershlick, Handbook of Drug-Eluting Stents (Taylor & Francis, London, New York, NY, 2005)Google Scholar
- 6.N. Everall, Spectroscopy 19, 22 (2004)Google Scholar
- 8.J. Fortin, T. Lu, Chemical Vapor Deposition Polymerization (Kluwer Academic, Dordrecht, 2003)Google Scholar
- 10.R. Hilfiker, Polymorphism in the Pharmaceutical Industry (Wiley-VCH, Weinheim, 2006)Google Scholar