Big Submarine launched (Belgorod project)
April 28, 2019
Big Eagles on moving
April 28, 2019
Synthetic Cartilage
April 28, 2019
Biomacromolecules. 2019 Apr 22.
doi: 10.1021/acs.biomac.9b00237. [Epub ahead of print]
Double Network Hydrogels that Mimic the Modulus, Strength and Lubricity of Cartilage.
Means AK, Shrode CS, Whitney LV, Ehrhardt DA, Grunlan MA.
Abstract
The development of a hydrogel-based synthetic cartilage has the potential to overcome many limitations of current chondral defect treatments. Many efforts have attempted to replicate the unique characteristics of cartilage in hydrogels, but none simultaneously achieved high modulus, strength and toughness while maintaining the necessary hydration required for lubricity. Herein, double network (DN) hydrogels, composed of a poly(2-acrylamido-2-methylpropane sulfonic acid) (PAMPS) 1st network and a poly(N-isopropyl-acrylamide-co-acrylamide) [P(NIPAAm-co-AAm)] 2nd network, are evaluated as a potential off-the-shelf material for cartilage replacement. While predominantly used for its thermosensitivity, PNIPAAm is employed to achieve superior mechanical properties and its thermal transition temperature tuned above the physiological range. These PNIPAAm-based DNs demonstrate a 50-fold increase in compressive strength (~25 MPa, similar to cartilage) compared to traditional single network hydrogels while also achieving a cartilage-like modulus (~1 MPa) and hydration (~80%). By directly comparing to healthy cartilage (porcine), these hydrogels are confirmed not only to parallel the strength, modulus and hydration of native articular cartilage but also exhibit a 50% lower coefficient of friction (COF). The exceptional cartilage-like properties of the PAMPS/P(NIPAAm-co-AAm) DN hydrogels makes them candidates for synthetic cartilage grafts for chondral defect repair, even in load-bearing regions of the body.
PMID:
31009565
DOI:
10.1021/acs.biomac.9b00237
