Drug delivery systems polymer implants

Uses Biodegradable polymer for plastics, films, rigid thermoformed food/beverage containers, coated papers, depth filters material for drug delivery systems surgical implants... 

These results open the exciting possibility of using degradable, tyrosine-derived polymers as "custom-designed" antigen delivery devices. On the other hand, our results indicate that the immunological properties of tyrosine-derived polymers will have to be carefully evaluated before such polymers can be considered for use as drug delivery systems or medical implants. 

F Lescure, D Bichon, JM Anderson, E Doelker, ML Pelaprat, RJ Gurny. Acute histopathological response to a new biodegradable polypeptidic polymer for implantable drug delivery system. Biomed Mater Res 23 1299-1313, 1989. 

Erdmann et al. (2000) report the fabrication of devices for the localized delivery of salicylic acid from the poly(anhydride-co-ester)s mentioned in Section II.C. A unique feature of this drug delivery system is that the drug compound is part of the polymer backbone. Devices were implanted intraorally and histopathology was reported (Erdmann et al., 2000). Chasin et al. (1990) review fabrication and testing of implantable formulations for other drugs including angiogenesis inhibitors for treatment of carcinomas and bethanechol for the treatment of Alzheimer s disease. 

Nondegradable subcutaneous implants as diffusion-controlled drug delivery systems, including Norplant, have been reviewed.89 99 Unlike biodegradable implants with long-term toxicological concern for metabolism of the polymer, nondegradable implants cannot avoid removal of the... 

Historically, polyanhydrides were synthesized for engineering materials. Because of their hydrolytical instability, these polyanhydrides have never been commercialized for engineering purposes. This instability has a beneficial aspect in drug delivery systems since the implant incorporated with an active drug does not need to be retrieved. The anhydride has a labile bond in the main chain of the polymer. This labile bond then breaks down into two carboxylic acid groups. 

Numerous microfabrication techniques have been used to produce a wide range of implantable and oral drug delivery systems using materials ranging from silicon, glass, silicone elastomer, and plastics. Fabrication techniques have rapidly evolved to produce nanoscale objects and therapeutic systems using polymeric materials as the substrate due to their biodegradable nature. There are a number of different synthetic polymer systems that have been developed for this type of application, and the most common ones are listed below ... 

De Ponti R, Torricelli C, Martini A, Lardini E. Use of supercritical fluids to obtain porous sponges of biodegradable polymers for pharmaceutical implants or drug delivery systems. Italy, WO 9109079, 1991. 

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