OG 488, SE (Oregon green 488 succinimidyl ester) is a fluorescent pH indicator, a fluorescein-based dye with many applications in biochemistry and neuroscience.

Physicochemical Properties

Molecular Formula	C25H13NO9F2
Molecular Weight	509.369
Exact Mass	509.06
Elemental Analysis	C, 58.95; H, 2.57; F, 7.46; N, 2.75; O, 28.27
CAS #	198139-51-4
PubChem CID	21252445
Appearance	Yellow to orange solid powder
LogP	2.6
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	11
Rotatable Bond Count	3
Heavy Atom Count	37
Complexity	963
Defined Atom Stereocenter Count	0
InChi Key	NIPUTGPBPLFCFM-UHFFFAOYSA-N
InChi Code	InChI=1S/C25H13F2NO9/c26-15-6-13-19(8-17(15)29)35-20-9-18(30)16(27)7-14(20)25(13)12-2-1-10(5-11(12)24(34)36-25)23(33)37-28-21(31)3-4-22(28)32/h1-2,5-9,29-30H,3-4H2
Chemical Name	(2,5-dioxopyrrolidin-1-yl) 2',7'-difluoro-3',6'-dihydroxy-3-oxospiro[2-benzofuran-1,9'-xanthene]-5-carboxylate
Synonyms	OG488 SE; OG 488 SE; OG-488 SE; OG488,SE; OG 488,SE; OG-488,SE
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: This product requires protection from light (avoid light exposure) during transportation and storage.
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

References

[1]. Absorption and emission study of 2',7'-difluorofluorescein and its excited-state buffer-mediated proton exchange reactions. J Phys Chem A. 2005 Feb 10;109(5):734-47.

Solubility Data

Solubility (In Vitro)

DMSO : ~100 mg/mL (~196.32 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 1.25 mg/mL (2.45 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 12.5 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: ≥ 1.25 mg/mL (2.45 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 12.5 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	1.9632 mL	9.8160 mL	19.6321 mL
	5 mM	0.3926 mL	1.9632 mL	3.9264 mL
	10 mM	0.1963 mL	0.9816 mL	1.9632 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.