Cytometry

Prior to analysis, cells are commonly stained to enhance contrast or to detect specific molecules by labeling these with fluorochromes.

This has led to the commercial availability of automated image cytometers, ranging from simple cell counters to sophisticated high-content screening systems.

To detect specific molecules when optically characterized, cells are in most cases stained with the same type of fluorochromes that are used by image cytometers.

[citation needed] In 1904, Moritz von Rohr and August Köhler at Carl Zeiss in Jena constructed the first ultraviolet microscope.

A filtering technique for fluorescence excitation light was developed by Heinrich Lehmann at Zeiss in 1910, based on work by Robert Wood.

At this time, Torbjörn Caspersson, working at the Karolinska Institute in Stockholm, developed a series of progressively more sophisticated instruments called cytophotometers.

These instruments combined a fluorescent microscope with a spectrophotometer to quantify cellular nucleic acids and their relation to cell growth and function.

[12] Joseph and Wallace Coulter circumnavigates these difficulties by inventing the principle of using electrical impedance to count and size microscopic particles suspended in a fluid.

Dittrich and Göhde’s pulse cytophotometer was built around a Zeiss fluorescent microscope and commercialized as the ICP 11 by Partec GmbH in 1968.

[17][18][19] Fulwyler, at Los Alamos as well, combines the Coulter principle with continuous inkjet printer technology to create the first cell sorter in 1965.

[21] In 1978, at the Conference of the American Engineering Foundation in Pensacola, Florida, the name pulse cytophotometry was changed to flow cytometry, a term which quickly became popular.

[22] At that point pulse cytophotometry had evolved into the modern form of flow cytometry, pioneered by Van Dilla ten years earlier.