561-nm Laser for Gallios Flow Cytometers

A 561-nm laser is available for the new 561-nm laser-ready Gallios flow cytometers from Beckman Coulter Life Sciences. It enables researchers to analyze a greater range of fluorescent proteins and to more efficiently excite phycoerythrin/phycoerythrin (PE) tandems. Optimal excitation is offered for red fluorescent proteins such as mCherry and DsRed, which are being increasingly used in research labs.

Yellow-green excitation provided at 561 nm produces less autofluorescence in cells, increasing the signal-to-noise ratio for PE and DsRed detection. Because 561-nm excitation is well separated from fluorescein and green fluorescent protein (GFP) emission, there is virtually no crossover contamination in the green detection channel, allowing simultaneous fluorescein or GFP detection without blocking optics.

The laser is externally coupled through an optical fiber and can be field-installed on Gallios analyzers. It will be passed to the flow cell collinearly with the 488-nm laser during acquisition.

Available configurations for the flow cytometers are: six color/two laser, eight color/two laser, 10 color/three laser and 10 color/four laser — with the last configuration reflecting the 561-nm option. Six fluorescence detectors provide simultaneous acquisition of up to six fluorescence signals. Concurrent measurements of integral, peak and width are available for all parameters, including scatter and fluorescence signals.

Gallios cytometers feature a forward-scatter detector that provides up to three measurements of cell size and visualization of particles down to 0.404 μm in diameter. A side-scatter detector incorporates an independently focused photodiode with electronic attenuation.

A selection of up to 62 parameters can be processed per analysis, at acquisition rates of 25,000 events per second, with high yield. Easily interchanged optical filters facilitate detection of a variety of dyes and wavelengths.

For more information, visit: www.beckmancoulter.com