Research

The MAP lab is dedicated to designing fluorescent and chromic (color-changing) materials to color-map the nanoscopic world with molecular resolution. The long-term goals are (1) to design dyes as single-molecule functional probes, (2) to develop single-molecule imaging and analytical methods for various man-made and native biological systems to decode nanofiber functions, and (3) to engineer chromic materials for smart and biomedical textiles.

*Background images show the microtubule nanofiber network of a retinal neuron spanning out for neuron signalling.

Current research projects are funded by the National Institute of Health (NIH, Grant R21GM141675, R35GM155241 and R01GM143397) and the National Science Foundation (NSF, Grant CHE-2441081 and CHE-2246548)

Development of Switchable and Functional Fluorescence Probes for Next-Generation Single-Molecule/Super-Resolution Microscopy

Making dye molecules fluoresce intermittently ("blinking") is the key to single-molecule/super-resolution microscopy (A Nobel-Price winning technique in 2014) to map the nano-world. This project aims to design and synthesize palettes of switchable fluorophores as molecular labels to image multi-molecular interactions. We seek to leverage the various choices of existing fluorescent dyes, probes, and indicators such as Cyanines, BODIPYs, Rhodamines and Luminescent nanoparticles and engineer their brightness, sensitivity in detecting different substances, fluorescence switching capability and bioorthogonal targeting ability towards imaging multiple molecules in the crowded nanoscopic world simultaneously. We also develop machine learning-based imaging processing and analytical methods to decode the imaging data to achieve this goal. Particular research questions including:

1) how to design fluorescent dyes/probes that are brighter, switchable and reporting nanoscale functions

2) what is the structure-function relationship between fluorophore conformations and local environments

3) how to integrate functional fluorescent probes with state-of-art optical microscope, imaging analytics and machine learning to decode nanoscopic functions

Single-Molecule Imaging Studies of Nanofibers and Macromolecules in Biological and Artificial Systems

Single-molecule studies can elucidate the otherwise overlooked spatial information and heterogeneities of important functions (e.g., biomolecular interactions, stoichiometry, dynamics ) as well as local environmental changes in functional materials (e.g., pH, polarity, charge, polarization). The long-term goal of this project is to understand the structure-function relationship between fluorescent probes and nanofibers using single-molecule imaging and spectroscopy in

1) how the 2-meter long DNA nanofibers in each cell pack into microscale chromatin higher-order conformation and further influence epigenome together with multi-scale studies of environmental impact on chromatin fiber in different biological processes

2) how cytoskeleton nanofibers (e.g., actin, microtubule, intermediate filaments, junction filaments) are affecting cellular processes such as adhesion and interacting with surrounding environments (e.g., textile-based biomaterials)

3) what is the nanoscale functional structures of artificial nanofiber (e.g., electron-spun nanoyarn) that lead to innovations in sustainability in the textile complex and renewable energy fields.

Chromic Materials for Smart and Biomedical Textiles

Chromic materials change their colors upon external stimulation such as light, temperature, electricity, mechanical force, and specific chemical substances (e.g., metal, pH). They have been widely used in our daily life such as photochromic sunglasses, temperature-color-changing water bottles and solar-activated fabrics and clothes. This project aims to design functional chromic materials with higher water-solubility, environmental friendly and high-valued smart and biomedical textiles

Previous Award/Projects:

NSF (CHE-1954430): Photochemical Strategies to Activate Far-Red Fluorescence with Green Light