In situ forming degradable networks and their application in tissue engineering and drug delivery.
Multifunctional macromers based on poly(ethylene glycol) and poly(vinyl alcohol) were photopolymerized to form degradable hydrogel networks. The degradation behavior of the highly swollen gels was characterized by monitoring changes in their mass loss, degree of swelling, and compressive modulus. Experimental results show that the modulus decreases exponentially with time, while the volumetric swelling ratio increases exponentially. A degradation mechanism assuming pseudo first-order hydrolysis kinetics and accounting for the structure of the crosslinked networks successfully predicted the experimentally observed trends in these properties with degradation. Once verified, the proposed degradation mechanism was extended to correlate network degradation kinetics, and subsequent changes in network structure, with release behavior of bioactive molecules from these dynamic systems. A theoretical model utilizing a statistical approach to predict the cleavage of crosslinks within the network was used to predict the complex erosion profiles produced by these hydrogels. Finally, the application of these macromers as in situ forming hydrogel constructs for cartilage tissue engineering is demonstrated.
Anseth
Kristi S
KS
Engineering Center, Room ECCH 111, Department of Chemical Engineering, University of Colorado, Boulder, CO 80309-0424, USA. kristi.anseth@colorado.edu
Metters
Andrew T
AT
Bryant
Stephanie J
SJ
Martens
Penny J
PJ
Elisseeff
Jennifer H
JH
Bowman
Christopher N
CN
D000818:Animals; D002356:Cartilage / Q000502:physiology*; D002417:Cattle; D006025:Glycosaminoglycans / Q000032:analysis; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000378:metabolism*; D006868:Hydrolysis; D011092:Polyethylene Glycols / Q000378:metabolism; D011142:Polyvinyl Alcohol / Q000378:metabolism; D013002:Somatomedins / Q000494:pharmacology; D023822:Tissue Engineering; D016212:Transforming Growth Factor beta / Q000494:pharmacology
D006025:Glycosaminoglycans; D013002:Somatomedins; D016212:Transforming Growth Factor beta; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D011092:Polyethylene Glycols; D011142:Polyvinyl Alcohol