Polyurethane drug delivery systems

Poly(propylene oxide) is typically obtained by base catalyzed anionic polymerization of propylene oxide [12]. Both stereospecific and atactic forms are known. The polymer is used as a soft polyether unit in polyurethane elastomers and foams in polymer electrolytes as surfactants (lubricants, dispersants, antistatic agents, foam control agents) in printing inks, as solubilizers in hydraulic fluids, coolant compositions in various medical applications (protective bandages, drug delivery systems, organ preservation, dental compositions), etc. 

Among the many classes of polymeric materials now available for use as biomaterials, non-degradable, hydrophobic polymers are the most widely used. Silicone, polyethylene, polyurethanes, PMMA, and EVAc account for the majority of polymeric materials currently used in clinical applications. Consider, for example, the medical applications listed in Table A.l most of these applications require a polymer that does not change substantially during the period of use. This chapter describes some of the most commonly used non-degradable polymers that are used as biomaterials, with an emphasis on their use in drug delivery systems. 

As we shall see in Chapter 15, polyurethane is a polymer of choice for a wide variety of biomedical applications. Polyurethane is used extensively in the construction of devices such as vascular prostheses, membranes, catheters, plastic surgery, heart valves, and artificial organs. Polyurethanes are also used in drug delivery systems such as the sustained and controlled delivery of pharmaceutical agents, for example, caffeine and prostaglandin. ... 

Polyurethane Good chemical resistance, toughness, good processabihty Catheters, tubing, LV. connectors, drug delivery systems... 

S. Moura, L. Lima, S. Andrade, A. Da Silva-Cunha, R. 6refice, E. Ayres, G. Da Silva, Local drug delivery system inhibition of inflammatory angiogenesis in a murine sponge model by dexameth-asone-loaded polyurethane implants, J. Pharm. Sci. 100 (7) (2011) 2886-2895. 

Vegetable oil-based hyperbranched polymers have considerable potential in biomedical applications. This is due to their unique structural characteristics along with their biodegradability and biocompatibiUty. Preliminary studies show that vegetable oil-based hyperbranched polyurethanes have the potential to be used as biomaterials in biomedical applications such as drug delivery systems, biomedical smart materials and catheters. ... 

Synthetic polymers have recently been examined for use in drug delivery systems. Polyesters, polyurethanes and polyanhydrides are among some of these synthetic polymers [3]. 

Degradable polyurethanes used in drug delivery systems... 

Chemg JY, Hou TY, Shih MF, Talsma H, Hennink WE. Polyurethane-based drug delivery systems. Int J Pharm 2013 450 145-62. 

Schierholz JM, Rump A, Pulverer G. New antiinfectious biomaterials. Ciprofloxacin containing polyurethanes as potential drug delivery systems to prevent foreign-body infections. Arzneimittelforschung Jannary 1997 47(l) 70-4. 

Chemg, J. Y, Hou, T.Y., Shih, M.F., Talsma, H., Hennink, W.E., 2013. Polyurethane-based drug delivery systems. International Journal of Pharmaceutics 450,145-162. 

Details are given of the development of novel implantable drug delivery systems based on segmented polyurethanes for the treatment of cancer diseases. Correlations between polymer molecular structure and release rate of vincristine are discussed. 7 refs. 

T.-E Chen, C.-M. Chiang, J. Jona, P. Joshi, and A. Ramdas, Polyurethane hydrogel drug reservoirs for use in transdermal drug delivery systems, WO Patent 1997009970 Al, 20 Mar 1997. 

In the late 1950s, polyacrylate-based PSAs were developed [283] and gained a dominant market share in the following decades. To a smaller extent polyfvinyi ethers) are used in medical devices. For specific applications like transdermal drug delivery systems, ostomy mounts, and electrically conductive adhesives a variety of specialty polymers such as silicones, polyurethanes, and various hydrogels are applied. 

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