UNIT 5.5 Measurement of Intracellular Ions by Flow Cytometry

  1. Carl H. June,
  2. Jonni S. Moore

Published Online: 1 DEC 2004

DOI: 10.1002/0471142735.im0505s64

Current Protocols in Immunology

Current Protocols in Immunology

How to Cite

June, C. H. and Moore, J. S. 2004. Measurement of Intracellular Ions by Flow Cytometry. Current Protocols in Immunology. 64:5.5:5.5.1–5.5.20.

Author Information

  1. University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania

Publication History

  1. Published Online: 1 DEC 2004
  2. Published Print: NOV 2004


The recent development of a number of new fluorescent probes makes it possible to measure the concentrations of various intracellular free ions in single living cells. Among these ions are calcium, magnesium, sodium, potassium, and hydrogen (pH). This unit describes flow cytometric protocols using the dyes Indo-1 AM, Fluo-3, and Fura Red AM to measure intracellular calcium concentration. Support protocols detail the use of calcium buffers to calibrate a flow cytometric calcium assay, and methods to facilitate dye loading; an alternate protocol describes the use of a spectrofluorimeter to measure intracellular calcium for those investigators without access to a flow cytometer.