Article

The effects of monoacrylated poly(ethylene glycol) on the properties of poly(ethylene glycol) diacrylate hydrogels used for tissue engineering.

Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Ave., Wickenden 309, Cleveland, Ohio 44106, USA.
Journal of Biomedical Materials Research Part A (impact factor: 2.63). 03/2009; 92(2):441-50. DOI:10.1002/jbm.a.32353 pp.441-50
Source: PubMed

ABSTRACT This study investigated the effects of poly(ethylene glycol) monoacrylate (PEGMA) on the properties of poly(ethylene glycol) diacrylate (PEGDA)-co-PEGMA hydrogel networks. The PEGMA materials utilized were similar to ligand-linked materials typically copolymerized with PEGDA for use as tissue engineering scaffolds. PEGDA (5-20% wt/wt, 6 kDa) and PEGMA (0-20% wt/wt, 0-43 mM, 5 kDa) were copolymerized by photo-initiated free radical polymerization and the mass swelling ratio and shear modulus of the resulting hydrogels were determined. Increasing the prepolymerization concentration of PEGMA decreased the swelling ratio by up to 42 +/- 1.6% and increased the shear modulus by up to 167 +/- 29.3%, suggesting that PEGMA enhanced gel cross-linking. Analysis of the effective number of cross-linked chains per PEGDA, calculated independently from swelling and mechanical data, indicated each PEGDA participated in more cross-links as PEGMA was added. The results suggest that PEGMA-co-PEGDA gels can be formed with higher concentrations of PEGMA-tethered ligands than previously reported allowing the formation of scaffolds with a rich diversity of biological functionalities without sacrificing the integrity of the gel network.

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Keywords

biological functionalities
 
cross-links
 
effective number
 
gel cross-linking
 
gel network
 
higher concentrations
 
ligand-linked materials
 
PEGDA
 
PEGDA)-co-PEGMA hydrogel networks
 
PEGMA materials utilized
 
PEGMA-co-PEGDA gels
 
photo-initiated free radical polymerization
 
poly(ethylene glycol)
 
prepolymerization concentration
 
resulting hydrogels
 
rich diversity
 
sacrificing
 
shear modulus
 
tissue engineering scaffolds
 

Jeffrey A Beamish