What is Flow Cytometry?

Flow CytometryFlow Cytometry is a technology for measuring cells or particles as they move in a liquid stream through a laser or light beam past the point of interrogation. Cytometry measures the relative light scattering and color discrimination fluorescence of the particles.

The cells are analyzed and differentiated based on size and granularity and whether the cell is carrying fluorescent molecules, either in the form of antibodies or dyes.

The modern flow cytometer consists of a light source, collection optics, electronics and a computer to translate signals to data. The light source of choice is a laser, which emits coherent light at a specified wavelength. Scattered and emitted fluorescent light is collected by two lenses, one set in front of the light source (forward scatter) and one set at right angles (side scatter) and by a series of optics, beam splitters and filters, specific bands of fluorescence can be measured.

Flow cytometers uses several types of laser — like the gas lasers (e.g. helium-neon, argon, helium-cadmium), solid state lasers (e.g. NdYAG), dye lasers or semi-conductor lasers.

The choice of fluorochrome to be used is influenced both by the application and the excitation wavelengths and the availability of an appropriate laser. It is possible to measure physical characteristics such as cell size, shape and internal complexity and any cell component or function that can be detected by a fluorescent compound. The applications of flow cytometry are numerous, and this has led to widespread use of these instruments in the biological and medical fields.


The Research and Translational Flow Cytometry and Immunology Core Laboratory at the University of Arizona College of Medicine – Phoenix provides expert analysis on state-of-the-art technology in flow cytometry, multiparameter cell sorting and analysis to investigators at the college, clinical laboratories and biotechnology companies throughout the State.    

Trained researchers are able to study complex cell populations through simultaneous multiparametric analysis of thousands of cells per second. High-speed assisted cell sorting services provide researchers objective quantitative recording of fluorescent signals from individual cells and full separation of particular cells of interest.


The Flow Cytometry and Immunology Laboratory offers an array of services across the spectrum of translational research, from basic medical science to clinical trials. These services include experimental design, sample preparation, data analysis and consultation and many other types of collaborative work. 


Research Applications

  • Immunophenotyping.
  • Cell sorting.
  • Cell cycle analysis.
  • Phosphorylated proteins.
  • Cytoplasmic/nuclear antigen analysis.
  • Apoptosis.
  • Cell proliferation assays.
  • Intracellular calcium flux.
  • Viability.
  • Cytometric bead array CBA technology.
  • FloCytoMix multiple analyte detection dystem.
  • Neurons.
  • Exosomes.