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Cat.No. 2919 - NPE-caged-HPTS | C24H14NO12Na3S3 | CAS No. 223759-19-1
Description: Caged fluorescent pH indicator
Chemical Name: 8-Hydroxypyrene-1,3,6-tris-sulfonic acid-8-1-(2-nitrophenyl)ethyl ether
Purity: ≥97% (HPLC)
Literature (1)

Biological Activity

Caged fluorescent pH indicator. Rapidly releases the fluorophore HPTS (pyranine) (pKa 7.25) upon two-photon excitation (>3000 s-1). Routinely used for photolysis calibration. Suitable for use in small-compartment diffusion studies.

Technical Data

M. Wt 673.53
Formula C24H14NO12Na3S3
Storage Store at -20°C
Purity ≥97% (HPLC)
CAS Number 223759-19-1
PubChem ID 56972217
Smiles [Na+].[Na+].[Na+].CC(OC1=C2C=CC3=C4C(C=CC(=C24)C(=C1)S([O-])(=O)=O)=C(C=C3S([O-])(=O)=O)S([O-])(=O)=O)C1=CC=CC=C1[N+]([O-])=O

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

Tocris products are intended for laboratory research use only, unless stated otherwise.

Solubility Data

Solvent Max Conc. mg/mL Max Conc. mM
water 67.35 100
DMSO 67.35 100

Preparing Stock Solutions

The following data is based on the product molecular weight 673.53. Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.48 mL 7.42 mL 14.85 mL
5 mM 0.3 mL 1.48 mL 2.97 mL
10 mM 0.15 mL 0.74 mL 1.48 mL
50 mM 0.03 mL 0.15 mL 0.3 mL

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

Willoughby et al (1998) Comparisons of simultaneous pH measurements made with 8-hydroxypyrene-1,3,6-trisulphonic acid (HPTS) and pH-sensitive microelectrodes in snail neurones. Pflugers Arch. 436 615 PMID: 9683736

Jasuja et al (1999) Chemotactic responses of Escherichia coli to small jumps of photoreleased L-aspartate. Biophys.J. 76 1706 PMID: 10049350

Kiskin et al (2002) The efficiency of two-photon photolysis of a "caged " fluorophore, o-1-(2-nitrophenyl)ethylpyranine, in relation to photodamage of synaptic terminals. Eur.Biophys.J. 30 588 PMID: 11908850

Bloodgood and Sabatini (2005) Neuronal activity regulates diffusion across the neck of dendritic spines. Science 310 866 PMID: 16272125

Trigo et al (2009) Laser photolysis of caged compounds at 405 nm: photochemical advantages, localisation, phototoxicity and methods for calibration. J.Neurosci.Methods 180 9 PMID: 19427524

Canepari et al (2001) Photochemical and pharmacological evaluation of 7-nitroindolinyl-and 4-methoxy-7-nitroindolinyl-amino acids as novel, fast caged neurotransmitters. J.Neurosci.Methods. 112 29 PMID: 11640955

Soler-Llavina et al (2006) Synapse-specific plasticity and compartmentalized signaling in cerebellar stellate cells. Nat.Neurosci. 9 798 PMID: 16680164

If you know of a relevant reference for NPE-caged-HPTS, please let us know.

Keywords: NPE-caged-HPTS, NPE-caged-HPTS supplier, Caged, fluorescent, pH, indicator, Fluorescent, Probes, Compounds, Ion, Indicators, Other, 2919, Tocris Bioscience

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