Live and Let Dye

Biochemistry. 2021 Nov 23;60(46):3539-3546. doi: 10.1021/acs.biochem.1c00299. Epub 2021 Jun 7.


The measurement of ion concentrations and fluxes inside living cells is key to understanding cellular physiology. Fluorescent indicators that can infiltrate and provide intel on the cellular environment are critical tools for biological research. Developing these molecular informants began with the seminal work of Racker and colleagues ( Biochemistry (1979) 18, 2210), who demonstrated the passive loading of fluorescein in living cells to measure changes in intracellular pH. This work continues, employing a mix of old and new tradecraft to create innovative agents for monitoring ions inside living systems.

Publication types

  • Historical Article

MeSH terms

  • Biochemistry / history*
  • Biochemistry / methods
  • Fluorescein / chemistry
  • Fluorescent Dyes / chemistry*
  • History, 20th Century
  • Hydrogen-Ion Concentration
  • Intravital Microscopy / history*
  • Intravital Microscopy / methods
  • Microscopy, Fluorescence


  • Fluorescent Dyes
  • Fluorescein