FLOW CYTOMETRY INSTRUMENTATION
H. B. Steen
Dept. of Biophysics
Cancer Research Institute
The Norwegian Radium Hospital
Oslo, Norway
INTRODUCTION
The uniqueness of flow cytometry lies in the ability to perform quantitative measurements of
individual cells in large numbers. By recording the fluorescence and light scattering of each
cell as it is carried through the excitation focus of the flow cytometer in the course of a few
microseconds, the cellular content of specific fluorescent constituents, or constituents that have
been fluorescently labelled, can be determined together with information relating to cell size
and structure. This ability to quantitatively characterize individual cells obviously has many
important applications in marine microbiology. Although flow cytometers have been used to
study marine microorganisms for several years, this field of applications is still in its infancy.
That may in part be due to the technical problems encountered when trying to put the flow
cytometer to work under the field conditions of a seagoing research vessel and on a type of
specimens which in some respects are quite different from what current instruments were
designed to handle. Flow cytometry was originally developed for measurement of cells in
immunology and research in the biology of mammalian cells. Although it is being applied in
other fields of biology as well, the bulk of applications is still limited to mammalian cells, a
fact which is reflected in the design of the instruments that are now on the market. The
majority of mammalian cells lie within a relatively narrow size range, i.e. 5 to 20 ~m. With
few exceptions they take on a spherical shape in suspension. They all have the same general
chemical composition, and any endogenous fluorescence they may have is typically only a
weak background, which is usually not a point of investigation in itself. Current flow
cytometers were designed to measure this kind of material within the benevolent conditions
of the typical research laboratory.
NATO AS] Series, Vol. G 27
Particle Analysis in Oceanography
Edited by S. Demers
© Springer-Verlag Berlin Heidelberg 1991
H. B. Steen
Dept. of Biophysics
Cancer Research Institute
The Norwegian Radium Hospital
Oslo, Norway
INTRODUCTION
The uniqueness of flow cytometry lies in the ability to perform quantitative measurements of
individual cells in large numbers. By recording the fluorescence and light scattering of each
cell as it is carried through the excitation focus of the flow cytometer in the course of a few
microseconds, the cellular content of specific fluorescent constituents, or constituents that have
been fluorescently labelled, can be determined together with information relating to cell size
and structure. This ability to quantitatively characterize individual cells obviously has many
important applications in marine microbiology. Although flow cytometers have been used to
study marine microorganisms for several years, this field of applications is still in its infancy.
That may in part be due to the technical problems encountered when trying to put the flow
cytometer to work under the field conditions of a seagoing research vessel and on a type of
specimens which in some respects are quite different from what current instruments were
designed to handle. Flow cytometry was originally developed for measurement of cells in
immunology and research in the biology of mammalian cells. Although it is being applied in
other fields of biology as well, the bulk of applications is still limited to mammalian cells, a
fact which is reflected in the design of the instruments that are now on the market. The
majority of mammalian cells lie within a relatively narrow size range, i.e. 5 to 20 ~m. With
few exceptions they take on a spherical shape in suspension. They all have the same general
chemical composition, and any endogenous fluorescence they may have is typically only a
weak background, which is usually not a point of investigation in itself. Current flow
cytometers were designed to measure this kind of material within the benevolent conditions
of the typical research laboratory.
NATO AS] Series, Vol. G 27
Particle Analysis in Oceanography
Edited by S. Demers
© Springer-Verlag Berlin Heidelberg 1991