In Situ Forming Poly(ethylene glycol)‐ Poly(L‐lactide) Hydrogels via Michael Addition: Mechanical Properties,Degradation, and Protein Release |
| |
Authors: | Sytze J. Buwalda Pieter J. Dijkstra Jan Feijen |
| |
Affiliation: | Department of Polymer Chemistry and Biomaterials, Faculty of Science and Technology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands |
| |
Abstract: | Chemically crosslinked hydrogels are prepared at remarkably low macromonomer concentrations from 8‐arm poly(ethylene glycol)‐poly(L ‐lactide) star block copolymers bearing acrylate end groups (PEG‐(PLLAn)8‐AC, n = 4 or 12) and multifunctional PEG thiols (PEG‐(SH)n, n = 2, 4, or 8) through a Michael‐type addition reaction. Hydrogels are obtained within 1 min after mixing PEG‐(PLLA4)8 ‐AC and PEG‐(SH)8 in phosphate buffered saline, quickly reaching a high storage modulus of 17 kPa. Lysozyme and albumin are released for 4 weeks from PEG‐(PLLA12)8‐AC/PEG‐(SH)8 hydrogels. Lysozyme release from PEG‐(PLLA12)8‐AC/PEG‐(SH)2 and PEG‐(PLLA12)8‐AC/PEG‐(SH)4 hydrogels is significantly faster with complete release in 3 and 12 d, respectively, as a result of a combination of degradation and diffusion. |
| |
Keywords: | biodegradable drug delivery systems hydrogels PEG‐PLLA star polymers |
|
|