Smart Granular Materials for Bioapplications
Research in the Yu Laboratory focuse on the engineering granular materials to manufacture biological systems and to develop biomedical applications. We design and synthesize molecular building blocks to build microgels, microcapsules, and vesicles with controllable macromolecular architecture and composition. Utilizing the tool of microfluidics as an experimental platform, we explore the interface between material science, synthetic biology and cell biology. As an interdisciplinary research team, we are good at a broad set of skills, including polymer synthesis, microfluidics, microencapsulation, cell culture, and additive manufacturing.

Dynamic  polymers  as  building  blocks for microencapsulation and delivery. The on-demand delivery of bioactive agents or cells is of great interest in a variety of biological applications, including targeted drug delivery, biocatalysis, cell therapies, and bioremediation. Using our expertise in supramolecular chemistry, we develop boronic acid-based microgels and cucurbit[8]uril-based host-guest complexes that able to encapsulate polypeptides, enzymes and microorganisms. The dynamics of the polymer building blocks provide tunable release rates of the payloads that can be tailored by pH, thermal, chemical, or photo stimuli. We are currently exploring novel dynamic building blocks and working towards their application in the preparation of microgels and microcapsules.

Vesicles for artificial cell mimics. The ability to build a synthetic cell will provide a simplified and controllable model to elucidate the cell’s intricate working and the original of life. By selecting a set of amphiphilic molecules, we use droplet-based microfluidics to form monodisperse, unilamellar, and cell-sized vesicles with excellent stability. To mimic the cellular membrane, we prepare the bilayers at the microdroplets interfaces or under the microdroplets dewetting, where the membrane transport channels are tuned by self-assembled cyclic peptide tubes. Further, we develop an artificial cell system that allows the in vitro expression of proteins in the compartmentalized vesicles, which could advance new application areas in biotechnology and biofabrication.

Droplet-based microfluidics for microbial screening. The usage of cell factories to produce molecules and materials opens a route for supporting future growth of food, industrial and pharmaceutical biotechnology. However, one area where the strong improvement is required to screen the microbial species with valuable metabolic properties in an efficient and a high-throughput manner. We operate state-of-the-art microfluidics for the growth of the microorganisms, and to sort them based on the fluorescent supramolecular assay, which is used for indicating certain types of secreted molecules from the microorganisms. This platform enables high throughput detecting and screening strains within a mutagenized population with desirable characteristics.

  1. Bioinspired hydrogel microfibres colour-encoded with colloidal crystals, Mater. Horiz., 2019, 6, 1938-1943.
  2. Supramolecular nested microbeads as building blocks for macroscopic self-Healing scaffolds, Angew. Chem. Int. Ed., 2018, 57, 3079–3083.
  3. Patterned arrays of supramolecular microcapsules, Adv. Funct. Mat., 2018, 28, 1800550.
  4. Monodisperse microcapsules self-assembled within microfluidic droplets: a versatile approach for supramolecular architectures and materials, Acc. Chem. Res., 2017, 50, 208-217.
  5. Supramolecular hydrogel microcapsules via cucurbit[8]uril host–guest interactions with triggered and UV-controlled molecular permeability, Chem. Sci., 2015, 6, 4929-4933.
  6. Interfacial assembly of dendritic microcapsules with host-guest chemistry, Nat. Comm., 2014, 5, 5772.