Cy5-SE (Cy5 NHS Ester) is a reactive dye used to label the amino groups of peptides, proteins, and oligonucleotides. Excitation wavelength (nm): 649, emission wavelength (nm): 670.

Physicochemical Properties

Molecular Formula	C₃₇H₄₃N₃O₁₀S₂
Molecular Weight	753.88
Exact Mass	753.239
CAS #	146368-14-1
Related CAS #	CY5-SE triethylamine salt;1497420-70-8
PubChem CID	126969923
Appearance	Dark purple to black solid powder
LogP	7.318
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	11
Rotatable Bond Count	13
Heavy Atom Count	52
Complexity	1720
Defined Atom Stereocenter Count	0
InChi Key	WXWLHDCCGVWTDZ-UHFFFAOYSA-N
InChi Code	InChI=1S/C37H43N3O10S2/c1-6-38-29-18-16-25(51(44,45)46)23-27(29)36(2,3)31(38)13-9-7-10-14-32-37(4,5)28-24-26(52(47,48)49)17-19-30(28)39(32)22-12-8-11-15-35(43)50-40-33(41)20-21-34(40)42/h7,9-10,13-14,16-19,23-24H,6,8,11-12,15,20-22H2,1-5H3,(H-,44,45,46,47,48,49)
Chemical Name	2-[5-[1-[6-(2,5-dioxopyrrolidin-1-yl)oxy-6-oxohexyl]-3,3-dimethyl-5-sulfoindol-1-ium-2-yl]penta-2,4-dienylidene]-1-ethyl-3,3-dimethylindole-5-sulfonate
Synonyms	Cy5 NHS Ester Sulfo-Cyanine5 Succinimidyl Ester
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: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light.
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

ln Vitro

Guide (the following is our proposed plan, this plan merely gives a guide and can be modified according to your individual needs). Binding of SELP analogues to Cy5-SE [1]. 1. Take 1 mL of 100 mM sodium bicarbonate buffer. 2. Quench reaction: mix 50 μL of 100 μg/mL SELP solution made of 1 M (pH 8.3) and 10 μL of 1.2 mg/mL Cy5 monomer composed of 10% DMSO. NHS ester was combined and kept on ice for 2 hours. 3. Load the reaction mixture onto a 1.5 mL Sephadex G-25 column, and centrifuge at 1050 g for 3 minutes to elute Cy5-labeled SELP. Note: 1. CY dye will not significantly interfere with peptides 2. Low amounts of sodium azide (≤3 mM or 0.02%) or thimerosal (≤0.02 mM or 0.01%). 3. Avoid utilizing buffers containing primary amines (such as Tris, glycine) or ammonium ions. They will compete with the protein to be tagged and impair labeling efficiency. 4. For dyes without activator, you need to use condensation solution (500 ug/mL) (25952-53-8) activator candle for future marking tests. 5. This product is solely for scientific research by professionals and may not be used for clinical diagnosis or treatment. 6. For your safety and health, please don a lab coat and wear a disposable overview for operation.

References

[1]. Array-Based High-Throughput Analysis of Silk-Elastinlike Protein Polymer Degradation and C-Peptide Release by Proteases. Anal Chem. 2016;88(10):5398-5405.

Solubility Data

Solubility (In Vitro)

DMSO : ~25 mg/mL (~33.16 mM) H2O : ≥ 5.88 mg/mL (~7.80 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (3.32 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 25.0 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: ≥ 2.5 mg/mL (3.32 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 25.0 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. Solubility in Formulation 3: 25 mg/mL (33.16 mM) in Saline (add these co-solvents sequentially from left to right, and one by one), clear solution; with ultrasonication (<60°C). Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O 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	1.3265 mL	6.6324 mL	13.2647 mL
	5 mM	0.2653 mL	1.3265 mL	2.6529 mL
	10 mM	0.1326 mL	0.6632 mL	1.3265 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.