Hybrid Multicomponent Hydrogels for Tissue Engineering

Abstract

Artificial ECMs that not only closely mimic the hybrid nature of the natural ECM but also provide tunable material properties and enhanced biological functions are attractive candidates for tissue engineering applications. This review summarizes recent advances in developing multicomponent hybrid hydrogels by integrating modular and heterogeneous building blocks into well-defined, multifunctional hydrogel composites. The individual building blocks can be chemically, morphologically, and functionally diverse, and the hybridization can occur at molecular level or microscopic scale. The modular nature of the designs, combined with the potential synergistic effects of the hybrid systems, has resulted in novel hydrogel matrices with robust structure and defined functions.

Synthesis of bioactive protein hydrogels by genetically encoded SpyTag-SpyCatcher chemistry

“…The past decade has witnessed a growing trend in hydrogel design that calls for systems capable of controlling the behavior of encapsulated cells by providing, sensing, and responding to biological signals (2). This design criterion demands a new level of craftsmanship from scientists and engineers who wish to incorporate biomolecular species, which may range in size and complexity from small molecules to multidomain proteins, into biomaterials (3). A promising approach to this challenge uses bio-orthogonal chemistry to introduce the species of interest with spatial and temporal control (4-7).…”

“…S5). Based on the equation G = ρRT/M c , where ρ is the polymer density (0.100 g/cm 3 for a 10 wt % network), an ideal network is predicted to have a storage modulus of 2.70 kPa at room temperature (298 K). The experimental storage modulus (∼0.3 kPa) is much lower than the predicted value, suggesting incomplete cross-linking or the formation of elastically ineffective loops.…”

Modulating Biofunctional starPEG Heparin Hydrogels by Varying Size and Ratio of the Constituents

“…Gels with higher starPEG to heparin ratio formed faster than those with lower ratios. Compared to previously reported biohybrid hydrogel systems [35,[39][40][41][42][43][44] that used heparin as a pendant group our system is characterized by significantly higher heparin concentrations in the swollen matrices. Thus, the highly charged glycosaminoglycan heparin influences the network properties.…”

Creating biomaterials with spatially organized functionality

“…Recent advances in biofabrication techniques and the development of new chemistries have significantly improved strategies to control the spatial arrangement of multiple features and components within a single scaffold. 8,[11][12][13][14] For example, photopatterning techniques can be used to create stiffness gradients within 3D hydrogels by tuning the degree of UV cross-linking, which can modulate cell spreading and proliferation on a single sample. 15 A similar technique utilizing multiphoton laser light spatially patterned multiple proteins to guide cell migration and differentiation within a single hydrogel.…”