Synthesis of novel functional poly(1,4-ketone)s bearing pendant bioactive moieties: an approach to design biocompatible materials

Abstract

The Pd-catalyzed polymerization of CO and monomers bearing bioactive molecules is a challenging route to produce bio-functionalized polyketones. This approach is attractive since it offers, in principle, a unique control of the polymer microstructure. A series of new monomers bearing biologically relevant moieties such as monosaccharides, amino acids, vitamin E, testosterone or gallic acid was prepared. The copolymerization reactions of CO and these biofunctional monomers afforded highly functionalized materials with well-defined structures and degrees of polymerization ranging from oligomers to macromolecules of low molecular weight. The polymerization results strongly depended on the monomer structure (bulkiness) and the number of heteroatoms present. Polyketones of high molecular weights, functionalized with 2-5 mol-% glucose, acetyglucosamine or tyrosine moieties were also accessible. These materials resulted from terpolymerization reactions of carbon monoxide, propylene and monomers bearing those moieties, respectively. [Pd(dppp)(NCCH3)2](BF4)2, a readily available and economically attractive catalyst as well as mild reaction conditions were applied for all experiments. In view of future bio-applications the biocompatibility of the novel co- and terpolymers was tested in vitro. The results of the assays applied proved the materials to be non-toxic and correspondingly biocompatible. The possibility to prepare polyketone-based scaffolds with flexible and elastic mechanical properties makes these polymers highly attractive for applications in the urogenital tract. Therefore samples of propylene-CO polymer functionalized with tyrosine moieties were seeded with urothelial cells and implanted in mice. These initial in vivo experiments revealed a high potential of polyketones to be used in urology.