Abstract: Gel-forming block copolymers were prepared comprising i) a central hydrophilic block consisting essentially of a divalent poly(ethylene oxide) chain and ii) two peripheral monocarbonate or polycarbonate hydrophobic blocks. The hydrophobic blocks comprise one or more vitamin-bearing subunits. The vitamin-bearing subunits comprise a carbonate backbone portion and a side chain comprising a covalently bound form of a vitamin. The gel-forming block copolymers can be used to prepare various biodegradable and/or biocompatible hydrogel and organogel drug compositions, in particular antimicrobial and/or anti-tumor drug compositions. The hydrogel compositions can be suitable for depot injections. Synergistic enhancement of toxicity to microbes was observed with compositions comprising an antimicrobial cationic polymer and an antimicrobial compound.

Abstract: Antimicrobial cationic polymers having one or two cationic polycarbonate chains were prepared by organocatalyzed ring opening polymerization. One antimicrobial cationic polymer has a polymer chain consisting essentially of cationic carbonate repeat units linked to one or two end groups. The end groups can comprise a covalently bound form of biologically active compound such as cholesterol. Other antimicrobial cationic polymers have a random copolycarbonate chain comprising a minor mole fraction of hydrophobic repeat units bearing a covalently bound form of a vitamin E and/or vitamin D2. The cationic polymers exhibit high activity and selectivity against Gram-negative and Gram-positive microbes and fungi.