Molecular Probes® sodium indicators allow spatial and temporal resolution of Na+ concentrations in the presence of physiological concentrations of other monovalent cations. These sodium indicators exhibit an increase in green fluorescence emission intensity upon binding Na+, with little shift in wavelength. 

Select sodium indicators

 

Indicators for Sodium

  • Measure steady-state changes in Na+ concentration
  • Track Na+ bursts in axons and presynaptic terminals

Indicators are available to estimate Na+ gradients in isolated mitochondria, to measure intracellular Na+ levels, to measure Na+ efflux in cells, and, in combination with other fluorescent indicators, to correlate changes in intracellular Na+ with Ca2+ and Mg2+ concentrations, intracellular pH, and membrane potential.

 

CA1 pyramidal neuron in a hippocampal slice filled with SBFICA1 pyramidal neuron in a hippocampal slice filled with SBFI delivered from a patch pipette.

Sodium Indicators Selection Guide

Used for spatial and temporal resolution of Na+ concentration and steady-state changes in sodium concentration, especially sodium/potassium ATPase studies. Also measures sodium bursts in axons and presynaptic terminals and axon initial segments.

 
ReadoutIncrease in green fluorescence emission intensity upon binding Na+, with little shift in wavelengthSpectral excitation shift used to estimate Na+ gradients in isolated mitochondria and intracellular Na+ levels
RangeResponds to a range of intracellular Na+ around 10 mMResponds to Na+ in physiological range
FluorophoreCoroNa™ GreenSBFI
Standard filter setFITCRequires excitation ratio to quantify Na+ levels
Ex/Em (nm)~492/516~340 and 380/500
BibliographyCitationsCitations
Cell permeant or impermeant?ImpermeantCell permeantImpermeantCell permeant
PlatformsImagingImagingImagingImaging
Usage notesLoad by microinjection, patch pipette, or pinocytic loading agentLoad in cell mediaLoad by microinjection, patch pipette, or pinocytic loading agentLoad in cell media
Format1 mg20 x 50 µg1 mg1 mg20 x 50 µg
Cat. No.C36675C36676S1262S1263S1264