Janelia Fluor^® 552, Haloalkane

Key Product Details

Product Description

Key Information: Janelia Fluor® 552, Haloalkane is a yellow cell-permeable fluorogenic dye with a chloroalkane handle. Also chemigenetic calcium indicator for imaging Ca²⁺ mediated responses. Upon self-labeling in WHaloCaMP modular biosensors, fluorescence output is modulated by photoinduced electron transfer (PET) to a protein based quencher.

Application: live-cell imaging as a self-labeling tag substrate. Suitable for confocal microscopy, light sheet microscropy, super resolution microscopy (SRM) techniques including dSTORM (in both live and fixed cells). In vivo functional imaging of Ca²⁺ responses (flies/mice); multiplexed functional imaging of neurons and astrocytes in zebrafish larvae; quantification of Ca²⁺ concentration using fluorescence lifetime imaging microscopy (FLIM).

Properties and Photophysical Data: Stable to fixation. Cell permeable. K_D = 87 ± 5. In the presence of EGTA (Ca²⁺ chelator) excitation and emission maxima (λ) are 561 nm and 559-578 nm, respectively; quantum yield = 0.05; extinction coefficient = 73,000 M^-1cm^-1 (measured in ethanol or TFE plus 0.1% TFA); brigthness = 3.6 mM^-1cm^-1. In the presence of saturating Ca²⁺, excitation and emission maxima (λ) are 562 nm and 565-582 nm, respectively; quantum yield = 0.25; extinction coefficient = 78,000 M^-1cm^-1 (measured in ethanol or TFE plus 0.1% TFA); brigthness = 19.5 mM^-1cm^-1.

Janelia Fluor^® is a registered trademark of Howard Hughes Medical Institute.

Licensing Information

Sold under license from the Howard Hughes Medical Institute, Janelia Research Campus

Optical Data

Product Specifications for Janelia Fluor^® 552, Haloalkane

The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis.

Solubility

Preparing Stock Solutions for Janelia Fluor^® 552, Haloalkane

The following data is based on the product molecular weight 696.18.

Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which all affect the solvent volumes required to prepare stock solutions.

Select a batch to recalculate based on the batch molecular weight:

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Concentration / Solvent Volume / Mass	1 mg	5 mg	10 mg
0.1 mM	14.36 mL	71.82 mL	143.64 mL
0.5 mM	2.87 mL	14.36 mL	28.73 mL
1 mM	1.44 mL	7.18 mL	14.36 mL
5 mM	0.29 mL	1.44 mL	2.87 mL

Calculators

Background References

References are publications that support the biological activity of the product.

• Zheng Rational design of fluorogenic and spontaneously blinking labels for super-resolution imaging. ACS Cent.Sci. 2019 PMID: 31572787
• Farrants A modular chemigenetic calcium indicator for multiplexed in vivo functional imaging. Nature Methods 2024 PMID: 39304767

Product Documents for Janelia Fluor^® 552, Haloalkane