1 - Poly(alkylene H-phosphonate)s

Abstract

Poly(alkylene H-phosphonate)s are a relatively new family of biodegradable, biocompatible, low toxic (1000 mg/kg) polymers that are being actively investigated for pharmaceutical and biomedical applications such as drug delivery and tissue engineering. A number of synthetic routes have been explored for the synthesis of these polymers, including ring-opening, bulk, and enzymatic polymerization, and bulk polycondensation. Structure and molecular weight of poly(alkylene H-phosphonate)s were determined by 1 H, 31 P, and 13 C NMR spectroscopy. They are particularly interesting due to the highly reactive P H group in the repeating unit that makes these polymers reactive and permits a number of chemical transformations to generate different materials from linear to cross-linked, from water-soluble to hydrophobic polymers, and from bio inert to bioactive. Oxidation and addition reactions to double bonds (carbon carbon, Schiff base, and carbonyl group) were discussed. Poly(alkylene H-phosphonate)s were used as a carrier of drugs—cysteamine, S -2(3-aminopropylamino) ethylphosphorothioic acid, 5-[(bis-(2-chloroethyl)amino]-1-methyl-benzimidazolyl-2-butyric acid (bendamustine), and 3′-azido-2′,3′-dideoxythimidine, and genes. Based on poly(alkylene H-phosphonate)s hydrogels with biodegradable phosphoester bonds were synthesized.