title: The effect of hypoxia on thermosensitive poly(N-vinylcaprolactam) hydrogels with tunable mechanical integrity for cartilage tissue engineering.
abstract: Cartilage repair presents a daunting challenge in tissue engineering applications due to the low oxygen conditions (hypoxia) affiliated in diseased states. Hence, the use of biomaterial scaffolds with unique variability is imperative to treat diseased or damaged cartilage. Thermosensitive hydrogels show promise as injectable materials that can be used as tissue scaffolds for cartilage tissue regeneration. However, uses in clinical applications are limited to due mechanical stability and therapeutic efficacy to treat diseased tissue. In this study, several composite hydrogels containing poly(N-vinylcaprolactam) (PVCL) and methacrylated hyaluronic acid (meHA) were prepared using free radical polymerization to produce PVCL-graft-HA (PVCL-g-HA) and characterized using Fourier transform infrared spectroscopy, nuclear magnetic resonance, and scanning electron microscopy. Lower critical solution temperatures and gelation temperatures were confirmed in the range of 33-34°C and 41-45°C, respectively. Using dynamic sheer rheology, the temperature dependence of elastic (G') and viscous (G″) modulus between 25°C and 45°C, revealed that PVCL-g-HA hydrogels at 5% (w/v) concentration exhibited the moduli of 7 Pa (G') to 4 Pa (G″). After 10 days at 1% oxygen, collagen production on PVCL-g-HA hydrogels was 153 ± 25 μg/mg (20%) and 106 ± 18 μg/mg showing a 10-fold increase compared to meHA controls. These studies show promise in PVCL-g-HA hydrogels for the treatment of diseased or damaged articular cartilage. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1863-1873, 2017.
authors.affiliation: Department of Chemistry, Morehouse College, Atlanta, Georgia.
authors.forename: Brandon
authors.initials: B
authors.lastname: Lynch
authors.affiliation: Department of Chemistry, Morehouse College, Atlanta, Georgia.
authors.forename: Kristopher
authors.initials: K
authors.lastname: Crawford
authors.affiliation: Department of Chemistry, Morehouse College, Atlanta, Georgia.
authors.forename: Omari
authors.initials: O
authors.lastname: Baruti
authors.affiliation: Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York.
authors.forename: Asem
authors.initials: A
authors.lastname: Abdulahad
authors.affiliation: Department of Chemistry, Morehouse College, Atlanta, Georgia.
authors.forename: Martial
authors.initials: M
authors.lastname: Webster
authors.affiliation: Department of Biomedical Engineering, Cornell University, Ithaca, New York.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Puetzer
authors.affiliation: Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York.
authors.forename: Chang
authors.initials: C
authors.lastname: Ryu
authors.affiliation: Department of Biomedical Engineering, Cornell University, Ithaca, New York.
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Bonassar
authors.affiliation: Department of Chemistry, Morehouse College, Atlanta, Georgia.
authors.forename: Juana
authors.initials: J
authors.lastname: Mendenhall
mesh_terms: D000818:Animals; D002209:Caprolactam / Q000031:analogs & derivatives* / Q000737:chemistry; D002358:Cartilage, Articular / Q000378:metabolism / Q000473:pathology; D002417:Cattle; D020100:Hydrogels / Q000737:chemistry*; D000860:Hypoxia / Q000378:metabolism / Q000473:pathology; D011108:Polymers / Q000737:chemistry*; D023822:Tissue Engineering; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D020100:Hydrogels; D011108:Polymers; C086861:poly-N-vinylcaprolactam; D002209:Caprolactam
keywords: chondrocyte; hyaluronic acid; hydrogel; hypoxia; smart material