Non-destructive evaluation of a new hydrolytically degradable and photo-clickable PEG hydrogel for cartilage tissue engineering
Alexander J. Neumann, Timothy P. Quinn, Stephanie J. Bryant
Photopolymerizable and hydrolytically labile poly(ethylene glycol) (PEG) hydrogels formed from photo-clickable reactions were investigated as cell delivery platforms for cartilage tissue engineering (TE). PEG hydrogels were formed from thiol-norbornene PEG macromers whereby the crosslinks contained caprolactone segments with hydrolytically labile ester linkages. Juvenile bovine chondrocytes encapsulated in the hydrogels were cultured for up to four weeks and assessed biochemically and histologically, using standard destructive assays, and for mechanical and ultrasound properties, as non-destructive assays. Bulk degradation of acellular hydrogels was confirmed by a decrease in compressive modulus and an increase in mass swelling ratio over time. Chondrocytes deposited increasing amounts of sulfated glycosaminoglycans and collagens in the hydrogels with time. Spatially, collagen type II and aggrecan were present in the neotissue with evidence of matrix connectivity beginning at day 21. Non-destructive measurements revealed an 8-fold increase in compressive modulus from days 7 to 28, which correlated with total collagen content and matrix connectivity. Ultrasound measurements revealed changes in the constructs over time, which differed from the mechanical properties, and appeared to correlate with ECM density. Overall, this new hydrolytically degradable PEG hydrogel is promising for cartilage TE leading to enhanced mechanical properties concomitant with matrix deposition and matrix connectivity.
, Quinn, T.
and Bryant, S.
Non-destructive evaluation of a new hydrolytically degradable and photo-clickable PEG hydrogel for cartilage tissue engineering, ACTA Biomaterialia, [online], https://doi.org/10.1016/j.actbio.2016.05.015
(Accessed May 30, 2023)