Microfluidic-Enabled Granular Biomaterials

Hydrogels prepared from biopolymers, such as collagen, elastin, fibroin, and gelatin (denatured collagen) hold a remarkable promise for tissue engineering and regenerative medicine. Hydrogel scaffolds typically have coupled porosity and stiffness and suffer from impaired nutrient and oxygen permeation when they are thick (e.g., >200 µm), limiting their applications in 3D tissue engineering. We have introduced a facile, universal strategy to convert macromolecules with orthogonal physicochemical responsivity, such as thermo-chemically crosslinkable biopolymers, into injectable bead-based scaffolds with a microporous structure. This technology eliminates the necessity of bioorthogonality for developing 3D macromolecular cell scaffolds.

We are highly interested in designing functional biomaterials in a bottom-up approach via breaking down bulk materials into small (micro/nanoscale) compartments, hand-pick them, and customize their assembly into meso/macroscale constructs with finely tuned structure-property relationships. These injectable microporous granular hydrogels open a myriad of new opportunities in healthcare, water, food, and energy sectors. We are currently focused on the tissue engineering, regenerative medicine, and biosensing applications of these novel hydrogels.

Beaded Protein Scaffolds

Providing a 3D microporous tissue-mimetic environment with independent stiffness and pore size for tissue engineering and regeneration.

Fluorescent microscopy image of cells adhering to the annealed GelMA beads and spreading among them in 3D. The microgel diameter is ~100 µm.

Microengineered Emulsion-to-Powder Technology (MEtoP)

Preserving the molecular, colloidal, and bulk properties of microgel/nanogel suspensions.

Transmission electron microscopy image of protein aerogels that are able to recuperate the properties of freshly-prepared annealable microgels upon resuspension in aqueous media. The aerogel diameter is ~50 µm.

Selected Publications

(3) ACS Applied Polymer Materials

Microengineered emulsion-to-powder (MEtoP) technology for the high-fidelity preservation of molecular, colloidal, and bulk properties of colloidal systems (Link)

A. Sheikhi,* D. Di Lisa, J. de Rutte, O. Akouissi, D. Di Carlo,* A. Khademhosseini*. 1:1935-1941. 2019.

(2) MethodsX

Modular microporous hydrogels formed from microgel beads with orthogonal thermo-chemical responsivity: Microfluidic fabrication and characterization (Link)

A. Sheikhi,* J. de Rutte, R. Haghniaz, O. Akouissi, A. Sohrabi, D. Di Carlo,* and A. Khademhosseini*. 6:1747-1752. 2019.

(1) Biomaterials

Microfluidic-enabled bottom-up hydrogels from annealable naturally-derived protein microbeads (Link)

A. Sheikhi, J. de Rutte, R. Haghniaz, O. Akouissi, A. Sohrabi, D. Di Carlo, and A. Khademhosseini. 192:560-568. 2019.

Other Technologies

Biocolloids and Biopolymers

Biomimetic Materials

Colloidal Gels