Drug Discovery, Design, and Delivery Research
Prof. Aryeh Weiss, of the Faculty of Engineering and member of the Nano Medicine Center at the Institute of Nanotechnology and Advanced Materials (BINA), uses fluorescent microscopy to track dynamic processes that will shed light on a drug candidate's potential activity in a living system.
Using high throughput screening with a fully automated widefield inverted fluorescence microscope and an on-scope incubator, Weiss and his team explore the interaction between targeted nano-particles and live prostate cancer cells. Their system can test dozens of targeting molecules in a single experiment.
In addition, Weiss's group is capable of acquiring and processing large quantities of digital image data. This enables them to analyze the large multidimensional datasets produced by timelapse experiments on live cells. This work is carried out in collaboration with life scientists and chemists, who often lack the tools required to effectively test and characterize their systems.
Photodynamic Therapy
Weiss's lab also uses this system to study dynamic processes in cells. One example is the study of photodynamic therapy (PDT) induced cell death. They observe not only the endpoints (eg, percent of cells that have died), but also various parameters such as cell morphology and membrane integrity as a function of time.
They are currently studying the synergistic effect of PDT and other types of chemotherapy, in the hope that the combination will be much more effective than each of the individual treatments.
Imaging and Microscopy Research
As part of the Laboratory for Fluorescence Dynamics, a national center of expertise which has been established at Bar Ilan, Weiss's lab has a system that can perform confocal fluorescence lifetime imaging (FLIM), phosphorescence lifetime imaging, fluorescence correlation spectroscopy (FCS), raster image correlation spectroscopy (RICS), as well as conventional confocal imaging.
This system includes dual confocal hybrid PMT detectors, as well as dual picosecond pulsed lasers, and is the most advanced system of its kind in Israel. His team is now capable of studying protein-protein interactions through fluorescence resonant energy transfer (FRET), protein mobility through FCS, as well as many other phenomena for which fluorescence lifetime is a marker.
Areas of Interest
Weiss's research interests include other methods of microscopy, image processing, and characterization of fluorescent materials. He plans to add a number of state-of-the-art techniques to his arsenal of microscopic methods. These include multiphoton microscopy, adaptive optics for deeper imaging, and various types of super-resolution microscopy.
DAPI stained cells (MeOH fixation, Prolong mounting medium) viewed with GFP filter cube. Left: Before exposure to 405nm excitation;Middle: after 2 minutes of 405nm excitation;Right after 4 minutes of 405nm excitation.
B16 melanoma cells were incubated with ALA and exposed to 405nm light. Top: Control; Bottom: 1 hr incubation. 3 left columns: 0,5,41 hrs post exposure. Right: fluorescence of H2A-mRFP (41 hrs post exposure). Only cells in the irradiated field died.