To achieve sharper image resolution with light-sheet microscopy deep inside the biological samples, the team used a process called two-photon excitation for the illumination. This process has been used previously to allow deeper imaging of biological samples; however, it usually is used to collect the image one pixel at a time by focusing the exciting light to a single small spot.
"The conceptual leap for us was to realize that two-photon excitation could also be carried out in sheet-illumination mode," says Thai Truong, a postdoctoral fellow in Fraser's laboratory and first author of the paper. This novel side-illumination with a two-photon illumination is the topic of a pending patent.
"With this approach, we believe that we can make a contribution to advancing biological imaging in a meaningful way," continues Truong, who did his Ph.D. training in physics. "We did not want to develop a fanciful optical imaging technique that excels only in one niche area, or that places constraints on the sample so severe that the applications will be limited. With a balanced high performance in resolution, depth, and speed, all achieved without photo-damage, two-photon light-sheet microscopy should be applicable to a wide variety of in vivo imaging applications." He credits this emphasis on wide applicability to the interdisciplinary nature of the team, which includes two biologists, two physicists, and one electrical engineer.
"We believe the performance of this imaging technique will open up many applications in life sciences and biomedical researchwherever it is useful to observe, non-invasively, dynamic biological process in 3D and with cellular or subcellular resolution," says Willy Supatto, coauthor of the paper and a former postdoctoral fellow in Fraser's laboratory (now at the Centre National de la Recher
|Contact: Deborah Williams-Hedges|
California Institute of Technology