Physical Entrapment of Proteins into Hydrogels General Principles and Release Mechanisms

1 Physical Entrapment of Proteins into Hydrogels General Principles and Release Mechanisms 

Release of multiple proteins through combination of mechanisms and rates 

Biomedical hydrogels that can deliver multiple proteins in a multimodal mode and provide desirable pore structure and porosity to potentially encapsulate cells, have considerable potential as future therapeutic tools in medicine. The use of protein-loaded microspheres embedded in the hydrogel structure is a common approach to multimodal protein delivery. 

Microparticles of acidic and basic gelatin were used as carriers for the individual delivery of two different growth factors and were embedded in a hydrogel matrix, composed of glycidyl methacrylated dextran (Dex-GMA)/gelatin. This hybrid system allowed the independent release of BMP-2 or IGF-1 that facilitated cell attachment, proliferation, metabolism, and osteoblastic differentiation of cells in a synergistic manner [127]. 

Fibrin hydrogels were complexed with heparin-functionalized PLGA nanoparticles for the release of VEGF for revascularization purposes [128]. 

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