Dynamic ratiometric imaging of cytosolic free Ca2+ in skeletal muscle cells using 340/385-nm light-emitting diode illuminators
Calcium-sensitive fluorescent indicators fall broadly into two categories, ratiometric (dual-wavelength) or single-wavelength indicators based on their response to a calcium elevation. Ratiometric indicators shift either their excitation or their emission wavelengths in response to calcium, allowing the concentration of intracellular calcium to be determined from the ratio of fluorescence emission
