The only microscope capable of routinely visualising molecular level dynamic processes at the cell membrane while maintaining optimum specimen incubation conditions has been introduced by Carl Zeiss
Only complete system for the visualization of dynamic processes at the cell membrane delivers three world firsts.
The Laser Tirf imaging system combines specimen incubation over the long time periods required in many live cell experiments with multi-colour Tirf, epi-fluorescence and transmitted-light contrasting techniques under laser safety conditions.
An incubation option may be specified for each of the four stage options (fixed, heating, mechanical and scanning).
The new microscope is the first to offer the combination of Tirf and transmitted-light contrasting techniques, such as DIC and brightfield, which enables sequential recording of two image pairs per second.
By selectively exciting cellular fluorophores adsorbed, adhered, or bound to the surface and combining it with conventional epi-fluorescence, researchers can relate surface effects to internal cellular structures.
The Laser Tirf is also the first Tirf system to offer rapid laser line changes, thanks to a fast, double filter wheel and includes AxioVision software that permits on-screen alignment without compromising laser safety.
The new optical system boasts a multi-line argon laser with wavelengths of 458, 488 and 514nm, ideal for living dyes such as CFP, GFP, YFP and mRFP.
Its unique geometry ensures that TIRF is maintained while switching wavelengths, a problem with other Tirf systems.
"Many key events in the cell occur at or close to membrane surfaces.
"Tirf (total internal reflection fluorescence) visualises these events without interference from areas deeper within the cell as the excitation field penetrates only 100 to 200nm into the specimen.
"However, until now, the procedure has been technically complex, extremely sensitive to the alignment of the laser beam and difficult to combine with complementary transmitted light observation techniques," comments Aubrey Lambert, marketing manager, Carl Zeiss UK.
"Combining this cutting-edge technology with the optimum environmental conditions necessary to allow the cells to survive the lengthy observations has, until the introduction of our Zeiss Laser TIRF system, presented microscopists with a severe challenge".
The Laser Tirf imaging system is based on the Zeiss Axiovert 200 research microscope.
It is ideal for applications that include the selective visualisation of cell/substrate contact regions, tracking secretion in living cells, measuring the binding rates of cell surface receptors, the examination of submicroscopic morphology, and single molecule experiments on molecular motors.
