Functionalized polymers for medical applications

#The present invention relates to synthetic, biodegradable, biocompatible polymers for use in pharmaceutical and medical applications and to compositions and medical devices containing such polymers.

#Both natural and synthetic polymers, including homopolymers and copolymers, which are both biocompatible and biodegradable in vivo are known for use in the manufacture of medical devices that are implanted in body tissue and that are absorbed or passed by the body over time. Examples of such medical devices include suture anchor devices, sutures, staples, surgical tacks, clips, plates, screws, drug-delivery devices, adhesion prevention films and foams, and tissue adhesives.

#Natural polymers may include catgut, cellulose derivatives and collagen. Natural polymers typically are absorbed by the body after enzymatic degradation of the polymers in the body.

#Alkyd polymers have been prepared by several known methods. For example, alkyd-type polymers were prepared by Van Bemmelen (J. Prakt. Chem., 69 (1856) 84) by condensing succinic anhydride with glycerol. In the “Fatty Acid” method (see Parkyn, et al. Polyesters (1967), Iliffe Books, London, Vol. 2 and Patton, In: Alkyd Resins Technology, Wiley-Interscience New York (1962)), a fatty acid, a polyol and an anhydride are mixed together and allowed to react. The “Fatty Acid-Monoglyceride” method includes a first step of esterifying the fatty acid with glycerol and, when the first reaction is complete, adding an acid anhydride. The reaction mixture then is heated and the polymerization reaction takes place. In the “Oil-Monoglyceride” method, an oil is reacted with glycerol to form a mixture of mono-, di-, and triglycerides. This mixture then is polymerized by reacting with an acid anhydride.

#The synthetic, biodegradable, biocompatible polymers utilized in the present invention are the reaction product of an α,β-unsaturated polybasic acid or derivative thereof, a monoglyceride, and a functional agent. Preferably, the polymers of the present invention are prepared by the polycondensation first of an α,β-unsaturated polybasic acid or derivative thereof with a monoglyceride to form an alkyd polyester polymer. The monoglyceride comprises reactive hydroxy groups and fatty acid groups.

#The alkyd polyester polymer is reacted with the functional agent to form the functionalized alkyd polyester of the present invention. The functional agent comprises a first functional moiety that is a strong nucleophile, such as a thiol or amine, that can react with the α,β-unsaturated acid through a Michael addition reaction, thus pending the functional agent to the polymer. A “strong nucleophile” is a molecule that is capable of donating an electron pair to an electrophile in a polar-bond forming reaction. Preferably, the strong nucleophile is more nucleophilic than H2O at physiologic pH.