Personal cytometers: Slow flow or no flow?

Abstract
Although some manufacturers have optimistically described instruments with prices in the 40,000 US dollars range as "personal cytometers", analogy with the personal computer suggests that the target price for a true "personal" cytometer should be under 5,000 US dollars. Since such an apparatus could find a wide range of applications in cytomics in both developing and developed countries, it seemed desirable to consider its technical and economic feasibility. Using resolution targets and a variety of fluorescent bead standards immobilized on filters and/or slides, we evaluated high-intensity LEDs as fluorescence excitation sources, relatively inexpensive CCD cameras as detectors, and 35 mm camera lenses and plastic low-power microscope optics for light collection in a simple, inexpensive low-resolution imaging cytometer. The components tested could be combined toproduce an instrument capable of detecting fewer than 10,000 molecules of cell-associated fluorescent label, and thus applicable to a broad range of cytometric tasks. Given the requirements for light sources, detectors, optics, mechanics, electronics and data analysis hardware and software, and the components presently available, it should be easier to reach the desired 5,000 US dollars price point with an image cytometer than with a flow cytometer.