Optical microscopy provides an essential window into the micrometer scale structure and dynamics of diverse systems ranging from simple colloidal suspension and biological cells to tissues and entire developing organisms. Most optical microscopy studies are limited to two-dimensional regions of interest. A typical method of characterizing three-dimensional structure relies on confocal point scanning techniques, which are very slow. Due to lack of appropriate techniques, high-spatial resolution imaging of fast dynamics of macro-sized samples remains uncharted territory. This project paves the way for overcoming this barrier. The resulting novel imaging technique named light-field light-sheet microscopy is tested and optimized with diverse samples ranging from quantifying dynamics and topological structure of three-dimensional active liquid crystals to imaging the whole-brain of a fruit fly during food-search. The design principles of the microscopy and the associated software analysis code are shared with scientific community. The imaging technique is also popularized through its inclusion in the Annual Santa Barbara Summer School in Quantitative Biology, where the participants receive the training in using the instrument.
By seamlessly merging the existing techniques of the multi-view selective plane illumination microscopy and the light-field microscopy, scientists are developing a new optical microscope capable of imaging millimeter-sized samples with isotropic point spread function. When compared to the fastest imaging times accessible to state-of-the-art selective plane illumination microscopes, the technique being developed increases the temporal resolution by almost two orders of magnitude. This opens up the possibility of three-dimensional, high-spatial-resolution imaging of macroscopic samples at frequencies as high as 5 Hz. The microscope is used to study a variety of samples that range from materials science, cell biology and neuroscience. In particular, scientist use the microscope to (1) elucidate the interplay between the topological structure and dynamics of motile disclination loops in three-dimensional active nematic liquid crystals, (2) quantify temporal propagation of strain deformations in active gels where stresses are generated by single molecular motors, (3) perform whole-brain imaging during food-search in D. melanogaster larvae, and (4) characterize a whole nervous system as it forms and activates in the embryogenesis of D. melanogaster.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
