Personal cytometers: Slow flow or no flow?

Background: Although some manufacturers have optimistically described instruments with prices in the US$40,000 range as "personal cytometers", analogy with the personal computer suggests that the target price for a true "personal" cytometer should be under $5,000. 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. Methods: 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. Results: The components tested could be combined to produce 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. Conclusions: 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 price point with an image cytometer than with a flow cytometer. (c) 2006 International Society for Analytical Cytology.