Total internal reflection fluorescence (TIRF) microscopy is a method that resolves molecular events specifically at or near the cell surface (see How It Works). Major microscope manufacturers, including Zeiss, Nikon, and Olympus, offer "turnkey" TIRF systems costing upwards of $100,000. But you can also upgrade an existing microscope to this capability.
Berhard Wehrle-Haller, who runs a bioimaging facility at the University Medical Center in Geneva, did exactly that. He already had an old Zeiss microscope, CCD camera, software, and 488-nm laser on hand; all he needed was the TIRF condenser, which he obtained for about $20,000 from TILL Photonics of Gräfelfing, Germany. Though TILL does the installation about half the time, Wehrle-Haller installed his hardware himself. "The toughest thing was to align the laser," he says, "but the rest was very simple. I was done in half an hour." Since then he's added a second laser, as well as system ...
