We develop photoresponsive inhibitors or "photopharmaceutical reagents" for high-precision control of cytoskeleton biology, ion channels & receptors. With spatiotemporally precise applications of light, the bioactivity of these reagents can be targeted spatially to particular cells or subcellular areas, and temporally by switching their activity on and off as needed. We also run conceptual research to build new frameworks for both the photochemical and pharmacological aspects of photoswitch-based biological control. Stay wavelength-tuned...

We develop chemical tools to interact selectively in live cells with key redox-active thiol/selenol enzymes, such as the thioredoxin system and GPxs. The key here is to avoid indiscriminate reactivity with any thiols, which we tackle by mechanism-based design of multistep reaction cascades where each step contributes kinetic and thermodynamic selectivity. We are also studying how exofacial thiol networks can be hijacked for controlling cellular entry of small molecules ("thiol-mediated uptake"), as well as cell-ECM interactions and cell migration. Just follow the electrons...

Optical imaging methods have driven much of the extraordinary progress in biology over the last 50 years. We are introducing new chemical concepts for imaging: (1) retrofitting known agents to create high-brightness, long-lived, and biologically innocent fluorophores; (2) leveraging molecular switches and motors to improve the linearity and photostability of NIR/SWIR photoacoustic imaging; (3) designing fluorogenic probe systems to report on cell permeability, and to integrate enzymatic activity.