Fluo-4FF, Pentapotassium Salt, cell impermeant

Catalog number: F23980

Molecular Probes™  Related applications: Cell Viability, Proliferation & Function | Cellular Imaging | Pharma & Biopharma | Target & Lead Identification & Validation

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Labeled calcium indicators are molecules that exhibit an increase in fluorescence upon binding Ca2+. Fluo-5F, fluo-5N, and fluo-4ff are analogs of fluo-4 with lower Ca2+-binding affinity, making them suitable for detecting intracellular calcium levels in the 1 µM to 1 mM range that would saturate the response of fluo-3 and fluo-4. Cells may be physically loaded with the cell-impermeant salt forms of these indicators using patch pipette or microinjection or our Influx™ pinocytotic cell-loading reagent. These indicators are compatible with excitation at 488 nm by argon-ion laser sources, making them useful for confocal microscopy, flow cytometry, and microplate screening applications.

Calcium Indicator (Cell-Impermeant Salts) Specifications:
• Label (Ex/Em of Ca2+–bound form): Fluo-4FF (494/516 nm)
• Fluorescence intensity increase upon binding Ca2+: >100 fold
• Kd for Ca2+ in buffer: ~9.7 µM
• Exhibit fluorescence increase upon binding Ca2+ with little shift in wavelength

Using TPEN to Control Heavy Metal Cations
In addition, BAPTA-based indicators such as these bind various heavy metal cations (e.g., Mn2+, Zn2+, Pb2+) with substantially higher affinity than Ca2+. Perturbations to calcium measurements caused by presence of these ions can be controlled using the heavy metal-selective chelator TPEN.

More Choices for Fluorescent Calcium Indicators
We offer a large selection of Molecular Probes® calcium indicators for use in various experimental scenarios. For more information, review Fluorescent Ca2+ Indicators Excited with Visible Light—Section 19.3 in the Molecular Probes® Handbook.

For UV-excitable Ca2+ indicators, protein-based Ca2+ indicators, conjugates of Ca2+ indicators, and for fluorescence-based indicators of other metal ions (i.e., Mg2+, Zn2+) review Indicators for Ca2+, Mg2+, Zn2+ and Other Metal Ions—Chapter 19 in the Molecular Probes® Handbook.

For Research Use Only. Not for human or animal therapeutic or diagnostic use.
For Research Use Only. Not for use in diagnostic procedures.


Indicator Type: Calcium Indicator
Indicator Properties: Fluorescent Dye-Based
For Use With (Equipment): Microplate Reader, Fluorescence Microscope, High Content Instrument, HTS Reader, Confocal Microscope, Fluorescent Imager
Cell Permeability: Cell-Impermeant
Product Size: 500 µg
Detection Method: Fluorescent
Shipping Condition: Room Temperature

Contents & storage

Store in freezer (-5 to -30°C) and protect from light.


Manuals & protocols

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