Pyranine

Pyranine is a hydrophilic, pH-sensitive fluorescent dye from the group of chemicals known as arylsulfonates.^[2][3] Pyranine is soluble in water and is used as a coloring agent, biological stain, optical detecting reagent, and pH indicator.^[4][5] Pyranine is also used in yellow highlighters to provide their characteristic fluorescence and bright yellow-green colour. It is also found in some types of soap.^[6]

Pyranine

Names
IUPAC name Trisodium 8-hydroxypyrene-1,3,6-trisulfonate
Other names 8-Hydroxypyrene-1,3,6-trisulfonic acid; Solvent Green 7; HPTS; Sulfonated hydroxy pyrene trisodium salt
Identifiers
CAS Number	6358-69-6 Y
3D model (JSmol)	Interactive image
Beilstein Reference	4107272
ChEBI	CHEBI:52083
ChemSpider	55317
ECHA InfoCard	100.026.166
EC Number	228-783-6
PubChem CID	4136521
UNII	I2W85YOX9L Y
CompTox Dashboard (EPA)	DTXSID4041739
InChI InChI=1S/C16H10O10S3.3Na/c17-11-5-12(27(18,19)20)8-3-4-10-14(29(24,25)26)6-13(28(21,22)23)9-2-1-7(11)15(8)16(9)10;;;/h1-6,17H,(H,18,19,20)(H,21,22,23)(H,24,25,26);;;/q;3*+1/p-3 Key: KXXXUIKPSVVSAW-UHFFFAOYSA-K
SMILES C1=CC2=C3C(=C(C=C2S(=O)(=O)[O-])S(=O)(=O)[O-])C=CC4=C(C=C(C1=C43)O)S(=O)(=O)[O-].[Na+].[Na+].[Na+]
Properties
Chemical formula	C16H7Na3O10S3
Molar mass	524.37 g·mol−1
Appearance	Yellow-green crystalline powder
Solubility in water	Soluble
Hazards
GHS labelling:[1]
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Synthesis

Pyranine is synthesized from pyrenetetrasulfonic acid and a solution of sodium hydroxide in water under reflux.^[7] The trisodium salt crystallizes as yellow needles when adding an aqueous solution of sodium chloride.

See also

• Fluorescein
• Fluorescence