Droplet microfluidics, in which micro-droplets serve as individual reactors, has enabled a range of high-throughput biochemical processes. Initial research on this technology demonstrated 1000-fold increase in throughput and up to 1 million-fold reduction in cost compared with state-of-the-art screening methods using microtiter plates. Our capability to form highly uniform drops at > 1kHz also enables us to generate complex fluids and soft matter bottom-up, and study how the microscopic structure of the material affects its bulk properties. Our research involves both fundamental and applied aspects: (I) Flow physics and collective behavior of croweded droplets in confinement. (II) Applications including rapid detection of pathogens for diagnosis of tuberculosis, and using bacteria to convert methane into bioplastics.
Our capability to synthesize novel nanoparticles to stabilize aqueous drops in fluorinated oils enables us to study a range of problems from interfacial transport to the mechanical properties of drops coated with these nanoparticles. Our particles have multiple advantages: 1) their synthesis is simple and scalable; 2) they are effective in stabilizing droplets against coalescence; 3) they prevent inter-drop molecular transport; and 4) their surfaces contain reactive groups such as amines that are capable of further conjugation with various “designer” molecules.
Inspired by tree rings—where the position of the ring indicates time, and the composition of the ring indicates historical environmental conditions—we are developing a new type of autonomous passive devices for simultaneous sensing and recording of time information. Initial applications can be in low-cost sensors such as smart labels to monitor the history of exposure to toxic chemicals in consumer/industrial safety products.
Wound healing and regeneration are essential biological processes for maintaining homeostasis and, ultimately, for survival. Cells, such as muscle cells, are regularly wounded in physiological conditions. These cells cannot be replaced easily in adults; self-healing is the only approach for restoring normal functions. Inability of a cell to heal can lead to serious diseases, such as muscular dystrophies. We are developing methods for controlled wounding and surgery of single cells, to enable systematic study of the biophysics behind wound healing and regeneration at the single-cell level.