Research

1. Synthesis of Ultra-bright Semiconducting Polymers and Preparation of Their Nanoparticle-Forms for Bioimaging and Sensing

Semiconducting polymer nanoparticles (Pdots) have emerged as an extraordinary fluorescent probe owing to their exceptional brightness, high photostability, fast radiative rate, and most importantly, facile functionalization. The proposed research is to develop a novel class of fluorescent nanoparticles called semiconducting polymer-based nanoparticles for bio-imaging, sensing, and photoswitching applications.

Dr. Quyen Nguyen’s research (working with Roger Tsien, Nobel Laureate in Chemistry) is focused on the development of fluorescently labeled probes for molecular navigation during surgery. Their first collaborative effort yielded a “smart” probe that makes tumors margins fluoresce, or “glow” and thus easier for surgeons to see and remove accurately during surgery. Their most recent joint effort resulted in another type of probe that can make nerves “glow” during surgery, thus helping surgeons repair injured nerves and avoid inadvertent injury.

She is a professor of surgery and director of the Facial Nerve Clinic at the University of California, San Diego.

2. Synthesis, Preparation and Characterization of Photoswitchable Self-Assembled Monolayers

Photochromic systems hold the promise of building molecular devices with photomechanical ability to convert light energy into mechanical energy. We are interested in understanding the fundamental processes in molecular switching and further development of light-controllable molecular devices. This proposed research is to systematically synthesize and investigate a series of photoswitchable assemblies on surfaces to gain the fundamental knowledge in photoswitching kinetics, conformational effect, and switching efficiency.

3. Using Patterned Arrays of Metallic Nanostructures to Create Plasmon Enhanced Devices and Their Applications for Biomolecular Detection

Here we present a simple platform for probing plasmon enhanced fluorescence of fluorophores. In this study, self-assembled monolayers of silane-derivative molecules were patterned onto the Si surfaces to direct the attachment of Au or Ag nanoparticles onto the surface. In this project, we are interested in investigating the parameters that can affect the plasmon enhancement and then use this platform to specifically probe molecules of interest.