FM™ 1-43 Dye (N-(3-Triethylammoniumpropyl)-4-(4-(Dibutylamino) Styryl) Pyridinium Dibromide)
FM&trade; 1-43 Dye (<i>N</i>-(3-Triethylammoniumpropyl)-4-(4-(Dibutylamino) Styryl) Pyridinium Dibromide)
Invitrogen™

FM™ 1-43 Dye (N-(3-Triethylammoniumpropyl)-4-(4-(Dibutylamino) Styryl) Pyridinium Dibromide)

FM 1-43 membrane probe is an excellent reagent both for identifying actively firing neurons and for investigating the mechanisms ofRead more
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Catalog NumberQuantity
T31631mg
T3535610 x 100μg
Catalog number T3163
Price (USD)
495.00
Each
Add to cart
Quantity:
1mg
Price (USD)
495.00
Each
Add to cart
FM 1-43 membrane probe is an excellent reagent both for identifying actively firing neurons and for investigating the mechanisms of activity-dependent vesicle cycling. This water-soluble dye, which is nontoxic to cells and virtually nonfluorescent in aqueous medium, is believed to insert into the outer leaflet of the cell membrane where it becomes intensely fluorescent. In a neuron that is actively releasing neurotransmitters, the dye becomes internalized within the recycled synaptic vesicles and the nerve terminals become brightly stained. The nonspecific staining of cell-surface membranes can simply be washed off prior to viewing. FM 1-43 membrane probe is also available as 1 mg in a single vial (T-3163). FM 1-43FX membrane probe (F-35355), an analog of FM 1-43 membrane probe that can be fixed in place using aldehyde-based fixatives, is also available.
For Research Use Only. Not for use in diagnostic procedures.
Specifications
ColorOrange
For Use With (Equipment)Fluorescence Microscope
Quantity1mg
Detection MethodFluorescence
Product LineFM™
Shipping ConditionRoom Temperature
Label TypeFluorescent Dye
Product TypeDye
SubCellular LocalizationPlasma Membrane
Unit SizeEach
Contents & Storage
Store at room temperature and protect from light.

Frequently asked questions (FAQs)

I want to study endosomes trafficking using FM 4-64. Will the label be retained after fixation? And can I label already-fixed cells?

No. For that you would need the FM 4-64FX version. The non-FX version will not be retained upon fixation, leading to loss of much of the stain and an increase in background. The FX version will be retained using an aldehyde-based fixative. Cells that are already fixed will be stained throughout the cell and the signal will not be localized; it is recommended to stain live cells and then fix.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

I want to study endosome trafficking using FM 4-64 dye. Will the label be retained after fixation? And can I label cells that have already been fixed?

No. For that, you would need the FM 4-64FX version. The non-FX version will be lost, leading to loss of much of the specific label and a vast increase in background labeling. The FX version will be fixed in place with formaldehyde. Cells that have been fixed already will not label correctly, so you will need to label the cells live and then fix.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

The product sheet for FM 1-43 Dye states that the maximum for excitation is 510 nm and emissions is 626 nm, but the spectrum on the product page shows a peak at 470 nm and 580 nm. Can you clarify what the excitation and emission maxima is for this dye?

FM lipophilic styryl dyes are known to shift their spectral properties upon binding to membranes. These dyes exhibit an appreciable solvent and environmental dependency in both free and membrane-bound forms. The emissions of the membrane-bound dye shifts to a shorter wavelength compared to the emission in the solvent.

In solvent, FM 1-43 Dye (Cat. Nos. T35356, T3163, F35355, F10317) absorbs in the range of fluorescein (~490 nm) and initially emits at around 626-636 nm. However, upon membrane integration, it exhibits emission in the 565-590 nm range. Because this dye exhibits a large Stokes shift, it does not perfectly fit into a green or orange fluorophore profile, but is rather a yellow-fluorescent dye, and may require a long-pass emission filter.

Note: FM 1-43 Dye is often used with typical fluorescein or GFP optical filter sets for biological imaging but is poorly excited through tetramethylrhodamine filters.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.