Colloidal Gels

Heterogeneous charge distribution imparts unique self-assembly capabilities to nanoclay-based colloidal systems. These colloidal gels are promising biomaterials for a broad range of biomedical applications, such as tissue engineering and therapeutic delivery. They can also undergo ion-mediated coacervate formation and phase separation, yielding new stimuli-responsive soft material platforms. Colloidal gels may further be combined with polyampholyte macromolecules to form reversible shear-responsive networks with fascinating self-healing properties. We aim at leveraging fundamental understanding of these colloidal systems for designing multi-functional biomaterials.

Colloidal Coacervates

Colloidal gels may undergo phase separation and coacervate formation under an stimulus, such as ionic strength fluctuation.

The phase separation of a colloidal gel into a biphasic system at varying concentrations of sodium chloride.

Heterogeneous Gels

While coacervates are a very interesting class of soft materials, they may not be favorable in injectable colloidal gels for minimally invasive medical procedures, such as endovascular embolization.

The heterogeneity of a colloidal gel reflected in the injection force.

Selected Publications

(2) Biotechnology Journal

Synthesis of injectable shear‐thinning biomaterials of various compositions of gelatin and synthetic silicate nanoplatelet (Link)

C. Xue, H. Xie, J. Eichenbaum, Y. Chen, Y. Wang, Floor W. van den Dolder, J. Lee, K.J. Lee, S. Zhang, W. Sun, A. Sheikhi, S. Ahadian, N. Ashammakhi, M.R. Dokmeci, H.‐J. Kim, A. Khademhosseini. Accepted. 2020.

(1) Biomaterials Science

Effect of ionic strength on shear-thinning nanoclay-polymer composite hydrogels (Link)

A. Sheikhi,§ S. Afewerki,§ R. Oklu, A.K. Gaharwar, and A. Khademhosseini. 6:2073-2083. 2018. Featured on the cover.

Other Technologies

Microfluidic-Enabled Biomaterials

Biocolloids and Biopolymers

Biomimetic Materials