Flow cytometry, an overview

Flow cytometry is a technique for making quantitative measurements on single cells or cellular constituents at very high rates of speed. The value of flow cytometry has been likened to finding a needle in a haystack. A measurement of the average property of a haystack would fail to identify the needle. One alternative is to measure each particle in the haystack one at a time using a parameter that would distinguish a piece of straw from something metallic. By measuring individual particles one can obtain a precise description of straw from something metallic, By measuring individual particles one can obtain a precise description of each particle from among a much larger population as illustrated in Figure 1.