Self-Degrading Multifunctional PEG-based Hydrogels - tailormade substrates for Cell Culture.

The use of PEG-based hydrogels as cell culture matrix to mimic the natural extracellular matrix (ECM) has been realized using a range of well-defined, tunable, and dynamic scaffolds, although they require cell adhesion ligands such as RGDS to promote cell adhesion. We herein demonstrate the synthesis of ionic and degradable hydrogels for cell culture by crosslinking [PEG-SH] 4 with the zwitterionic crosslinker N,N-bis(acryloxyethyl)-N-methyl-N-(3-sulfopropyl) ammonium betaine (BMSAB) and the cationic crosslinker N,N-bis(acryloxyethyl)-N,N-dimethyl-1-ammonium iodide (BDMAI). Depending on the amount of ionic crosslinker used in gel formation, the hydrogels showed tunable gelation time and stiffness. At the same time, the ionic groups act as catalysts for hydrolytic degradation, thereby allowing to define a stability window. The latter could be tailored in a straightforward manner by introducing the non-degradable crosslinker tri(ethylene glycol) divinyl ether. In addition, both ionic crosslinkers favour cell attachment in comparison to the pristine PEG hydrogels. The degradation was examined by swelling behaviour, rheology, and fluorescence correlation spectroscopy indicating degradation kinetics depending on diffusion of incorporated fluorescent molecules. This article is protected by copyright. All rights reserved.