ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Rheological properties of functionalised thermosensitive copolymers for injectable applications in medicine

Ivana Chamradová, Lucy Vojtová, Lenka Michlovská, Petr Poláček, and Josef Jančář

Institute of Materials Chemistry, Faculty of Chemistry, Brno University of Technology, Purkyňova 118, 612 00 Brno, Czech Republic

E-mail: xcchamradova@fch.vutbr.cz

Abstract: Functionalised triblock copolymers based on poly((lactic acid)-co-(glycolic acid)) and poly(ethylene glycol) (PLGA-PEG-PLGA) further modified with 3-methylenetetrahydrofuran-2,5-dione (itaconic anhydride; ITA) exhibited sol-gel transition induced by increasing temperature. Rheological properties of a series of ITA/PLGA-PEG-PLGA/ITA copolymer concentrations (6–24 mass %) in deionised Milli-Q water were studied by both the test tube inverting method (TTIM) and rheometer. The gel stiffness increased with the polymer concentration shifting the gel point of the copolymer to the lower temperature. The present study demonstrates that each method describes a sol-gel transition, but the combined method gives comprehensive information about changes in colour, viscosity, elastic and loss moduli. Characterisation of such a gel is necessary for its further use, in order to determine whether the material is appropriate as an injectable biomedical hydrogel.

Keywords: thermosensitive copolymers – test tube inverting method – rheology – sol-gel transition

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-012-0210-y

Chemical Papers 66 (10) 977–980 (2012)