Amine-Functionalized Polylactide-PEG Copolymers

Arican M. O. , Erdogan S., MERT O.

MACROMOLECULES, vol.51, no.8, pp.2817-2830, 2018 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 51 Issue: 8
  • Publication Date: 2018
  • Doi Number: 10.1021/acs.macromol.7b02751
  • Title of Journal : MACROMOLECULES
  • Page Numbers: pp.2817-2830


The formation of halogenated carboxylic acid intermediate followed by a ring-closing reaction led to amino-functionalized asymmetrical lactide monomer. PEG-based functional diblock and triblock polylactides were synthesized via a controlled ring-opening polymerization in a solvent-free medium with high conversions (up to 96%), low polydispersities as low as 1.06, monomodal GPC traces, and short reaction time (only 1 h). No polymerization of symmetrical monomer, synthesized via condensation of (S)-(+)-CBZ-4-amino-2-hydroxybutyric acid, proved that the preferred site in the mechanism of ring-opening polymerization was found as a methyl site in asymmetrical lactide monomer. A highly efficient deprotection of copolymers was carried out in the presence of H-2 gas and Pd/C catalyst without any degradation to obtain the corresponding free amine-functionalized aliphatic poly(alpha-hydroxy acid)s. These biodegradable thermosensitive polymers, suitable for any local therapy applications, were injectable around 42 degrees C (sol) and a gel just after cooling to body temperature. Faster hydrolytic degradation (up to 47% in 30 days) and more effective paclitaxel release from copolymer gels (up to 95% in 20 days) than well-known conventional PEG PLA gels may make functional lactides a preferred candidate for developing controlled/sustained release of drugs from delivery vehicles.