Smart Hybrid Hydrogels for Cartilage Repair


Cartilage tissue engineering requires scaffolds with superior rheological properties. Poly(N-isopropylacrylamide) (PNIPAm)-based scaffolds possess many desirable properties required for tissue regeneration. However, insufficient mechanical, strength, biocompatibility, and biomimicry hinder their application in tissue regeneration.

Researchers at the University of Calgary have developed a novel method to synthesize thermo-responsive, smart hydrogels consisting of an interpenetrating polymer network of amorphized cellulose grafted in PNIPAm, which results in superior mechanical properties and increased expression of chondrogenic markers.

Cellulose is the most abundant naturally occurring polymer; it is renewable and biodegradable, and suitable for various biomedical applications. This invention uses a simple treatment to modulate the crystallinity of cellulose, which allows to adjust the biocompatibility and viscoelasticity of the hybrid microgels, resulting in smart hydrogels that more closely resemble the natural cartilage. The novel synthesis is also more sustainable, reducing up to 97% of carbon emissions associated with production, in less toxic and environment friendly conditions.



  • This microgel scaffold can provide an excellent biocompatible microenvironment for cartilage tissue engineering.
  • This microgel can be used as a carrier for the target-specific delivery of encapsulated drugs.



  • Safe and environment friendly method suitable for biomedical applications.
  • Porous, mechanically robust, and suitable for cartilage tissue engineering.