Projects
Development of a Scan-less Temporal Focusing Two-photon Fluorescence Microscope for High-speed Three-dimensional Imaging (supported by NSF)
Project Description: This project will develop a high-speed temporal focusing two-photon fluorescence microscope for three-dimensional volumetric imaging without laser beam scanning. To achieve these two exceptional capabilities, high-speed and 3D volumetric imaging, two separately developed ultrafast laser techniques, temporal focusing and pulse shaping, will be integrated together for the first time.
Super Resolution Pump-Probe Microscopy for Biomedical Imaging (supported by NIH)
Project Description: This research is to develop new technology to do super resolution biomedical imaging modality, which will greatly enhance our ability to detect, visualize and quantify non-fluorescent molecules at nanometer resolution. To study single molecules in chemistry and biology with optical microscope, current techniques require labeling fluorescent molecules onto the target molecule we are interested in. However, this labeling cause a lot difficult in processing and the labeled molecule may interfere with the target molecule function. Therefore it is important to eliminate labeling and directly image the target molecule. By using the pump-probe method the non-fluorescent molecular could be detected directly in super resolution.
Nanoscale Transient Absorption Spectroscopy to Study Ultrafast Carrier Dynamics in Organic Solar Cells (supported by NSF)
Project Description: This research is to develop a nanometer resolution transient absorption microscope to study the charge-transfer states dynamics in bulk heterojunction organic solar cells. The goals are: 1) Develop a normal transient absorption spectroscopic method on solar cell study. This is the learning process to repeat some results obtained before. 2) Add another depletion beam and a phase mask to modulate the beam. The innovation part of this project is to break the current record.
Laser Induced Photochemistry for Micro-channels in Tissue Engineering (supported by ORSP IDR)
Project Description: Three-dimensional (3D) matrixes of novel peptide materials with built-in light-sensitive linkers can be "carved out" by precise laser irradiation to produce micro-channels, in which endothelial cells can grow into tubular structures. Our preliminary data indicate that photo-cleavable N-acyl-nitroindoline is a suitable two-photon absorber, that undergoes the desired photolytic cleavage when irradiated with a focused 700 nm femtosecond laser beam. While two-photon absorption and bond breakage by photolysis are well-known phenomena in optical physics and photochemistry, until now no materials were available that could utilize laser photolysis for the generation of channels in a three-dimensional matrix for tissue engineering. Here we generate novel collagen-like photo-reactive peptides, which will form a gel matrix into which micro-channels can be engineered with a femtosecond infrared laser. This highly interdisciplinary project requires chemistry, physics, and bioengineering, and has the potential to result in ground-breaking new technology for tissue engineering.