The single laser eliminates the complexity of a second light source, although users can add a second collinear, 20-mW, He-Ne laser (633 nm) to allow additional experimental permutations without the complications of time delay common to staggered dual-laser alignment.
Maria Daly, research biologist in the immunotherapeutics department at GlaxoSmithKline in Stevenage, UK, performs four-colour immunophenotyping of lymphocytes and dendritic cells with Beckman-Coulter's Epics XL single-laser flow cytometer. Now testing the single-laser FC 500 with a fifth fluorochrome, she commended the instrument's sensitivity: she was looking at a marker that is very weakly expressed in a particular B-cell subset which, when using the new system, was very well resolved.
Five-colour analyses are traditionally difficult, Daly says, because of spectral overlap. But the FC 500's 20-bit electronic capturing allows researchers to collect more information over a range of fluorescent intensity. It is also a cleaner system with much less distortion. Once they have scanned a sample, researchers can perform colour compensation in list-mode analysis. Thus, if you have undercompensated during the run, you can clean it up afterward using the software.
The Cytomics FC 500 runs on a Windows 2000 platform and features an Auto Setup Wizard, which increases quality control and user efficiency, says Howes. The Wizard automates machine calibration by setting voltages and gain, calculating compensation requirements, and verifying instrument settings.
In addition, the Cytomics FC 500 incorporates multiuser login capacity coordinated by the administrator. Derek Davies, Resource Service Manager of the FACS Laboratory at Cancer Research UK's London Research Institute, describes this as a useful feature, which allows each user to customize his or her set up and simplifies time logging for billing in those labs that need it. Depending on the configuration, the FC 500 costs between $160,000 and $170,000 (US).
For more information contact:
Beckman Coulter Inc.
+ (800) 526-3821
www.beckmancoulter.com
The Scientist - Lab Consumer
24 June 2002



