Voltage-sensitive dye

[2] Potentiometric dyes are used to monitor the electrical activity inside cell organelles where it is not possible to insert an electrode, such as the mitochondria and dendritic spine.

A change in the voltage across the membrane will therefore cause a spectral shift resulting from a direct interaction between the field and the ground and excited state dipole moments.

It has been applied to measure the action potentials of a single t-tubule of cardiomyocytes by Guixue Bu et al.[7] More recently, a series of fluorinated ANEP dyes was introduced that offer enhanced sensitivity and photostability; they are also available over a wide choice of excitation and emission wavelengths.

Potentiometric Probes, LLC specializes only in voltage sensitive dyes; they have an exclusive license to distribute the large set of fluorinated VSDs, marketed under the ElectroFluor brand.

[11] Strengths of imaging brain activity with voltage-sensitive dyes include the following abilities: Weaknesses of imaging brain activity with voltage-sensitive dyes include the following problems: Voltage-sensitive dyes have been used to measure neural activity in several areas of the nervous system in a variety of organisms, including the squid giant axon,[19] whisker barrels of the rat somatosensory cortex,[20][21] olfactory bulb of the salamander,[22][23][24] visual cortex of the cat,[25] optic tectum of the frog,[26] and the visual cortex of the rhesus monkey.

[27][28] Many applications in cardiac electrophysiology have been published, including ex vivo mapping of electrical activity in whole hearts from various animal species,[29][30] subcellular imaging from single cardiomyocytes,[31] and even mapping both sinus rhythms and arrhytmias in open heart in vivo pig,[18] where motion artifacts could be eliminated by dual wavelength ratio imaging of the voltage sensitive dye fluorescence.