Pitt | Swanson Engineering

A Systematic Engineered Approach to Controlled Degradation of Hydrogel 

Hydrogels of biopolymers are attractive vehicles for proteins, drugs and cells delivery due to their excellent biocompatibility along with the possibilities of tailoring the release characteristics. However, the slow and uncontrollable degradation of hydrogel are major roadblocks for its successful clinical applications in regenerative medicine. Enzymatic degradation of alginate gels using alginate lyase is fast evolving as an increasingly popular alternative to dissolution of gels, and lyases have been effectively applied in a variety of studies. In this project an enzyme aggregate of alginate lyase (EC 4.2.2.3) from flavobactierium was prepared using ammonium sulfate. The resultant aggregates upon cross-linking with glutaraldehyde produced insoluble and catalytically active cross-linked enzyme aggregate (CLEA) enzyme. The catalytic activity and stability of the cross-linked enzyme aggregate of alginate lyase (CLEA-AL) was studied in the presence of various pH, temperatures and organic solvents. Reusability, storage stability and surface morphology of the CLEA-AL were also studied. By encapsulating CLEA-AL into alginate hydrogel, we demonstrate that alginate hydrogels can be enzymatically degraded in a controlled fashion. The results also showed that degradation of alginate hydrogel with CLEA-AL incorporated beads is slower than native enzyme and therefore, CLEA-AL can be used for controlled degradation and release of various biologics from the degrading gel.

A Systematic Engineered Approach to Controlled Degradation of Hydrogel

Diagrammatic representation of CLEA preparation and use in hydrogel degradation.

1. INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES 115, 176–184 (2018)