Cyanine5.5 amine does not have a specific pharmacological target as it is a fluorescent dye. Its function is to absorb light in the near-infrared region and emit fluorescence, which can be used to detect and visualize biological molecules or processes. The compound's near-infrared fluorescence allows for deep tissue imaging with low background fluorescence. The amine group provides a reactive handle for conjugation to biomolecules, enabling the labeling of proteins, antibodies, or other targets for imaging applications.

In vitro, Cyanine5.5 amine is used as a fluorescent dye for labeling and imaging applications. It exhibits strong fluorescence in the near-infrared region (Ex/Em = 648/710 nm). The dye is used in fluorescence microscopy and flow cytometry to detect labeled biomolecules. It can be used to prepare Cy5.5-labeled nanoparticles for tracking and imaging with low fluorescence background using confocal microscopy. The dye's high sensitivity and photostability make it suitable for quantitative fluorescence-based assays.

Cy5.5-labeled nanoparticles (Cy5.5-PLGA) in retinal blood vessels: real-time monitoring. Advice (This is our suggested protocol, which should be adjusted to meet your unique requirements as it only offers guidance) [2]. 1. Give freshly made Cy5.5-PLGA suspension intravenously (0.5 mL); resuspend in 0.5 ml of 1% Poloxamer 188; vortex gently and let sit at room temperature for 30 minutes before using. 2. Rats are anesthetized, the iris is relaxed with 5% neosynephrine-POS, and Vidisic eye gel is applied to prevent dry eyes and to act as a soaking medium for contact lenses. 3. With the rat's eyes at working distance below the objective lens, place it under a confocal scanning microscope and place the cannula into the vein in its tail. 4. Take pictures and record retinal fluorescence at various intervals (0, 1, 3, 5, 15, 30, 60, 90 minutes). NOTE: Throughout every step of the in vivo imaging process, the rats stay on the heating plate. 5. The rat should be put to death with an overdose of the aforementioned anesthetic after in vivo real-time imaging. The eyeball should then be removed and placed in a cooled HEPES buffer solution (135 mM NaCl, 5 mM NaOH, 2.5 mM KCl, 7 mM MgCl2, 10 mM HEPES, 10 mM glucose; pH7.4). 6. The entire retina should be carefully separated, the anterior segment and vitreous body removed, and it should be laid flat on a modified culture plate. 7. To stain the nuclei, incubate the entire mount in 0.1 mg/mL Hoechst 33342 in HEPES solution for 20 minutes. 8. After 20 minutes of fixing flat-mounted retinas with 4% paraformaldehyde solution, wash with HEPES solution. 9. As soon as the retinal plain slide is ready, use the microscope to take a picture.
In vivo, Cyanine5.5 amine is used for near-infrared fluorescence imaging. Its fluorescence wavelength (Em: ~700 nm) falls within the near-infrared window I of tissue, where background fluorescence is low and tissue penetration is high. This makes Cy5.5 suitable for small animal in vivo imaging. The dye can be used to label various molecules for tracking their distribution, targeting, and accumulation in living animals. It is used in research to study tumor targeting, drug delivery, and other biological processes in vivo.

In vitro experiments with Cyanine5.5 amine typically involve preparing stock solutions in DMSO or other suitable solvents and diluting them in aqueous buffers for labeling reactions. For protein labeling, the dye is incubated with the protein of interest in a buffer at a suitable pH (e.g., pH 8.0-9.0) for 1-2 hours. The labeled protein is then purified by dialysis or size exclusion chromatography. The degree of labeling is determined by measuring the absorbance of the dye at 648 nm and the protein concentration. The labeled protein can then be used in various assays, including fluorescence microscopy, flow cytometry, or in vivo imaging.

In vitro cell-based assays using Cyanine5.5 amine are performed to study cellular uptake, labeling, and imaging. Cells are incubated with Cy5.5-labeled molecules (e.g., antibodies, peptides, nanoparticles) for a specified period. After washing, the cells are analyzed by fluorescence microscopy or flow cytometry using excitation at 648 nm and emission at 710 nm. The dye's near-infrared fluorescence allows for detection with minimal background autofluorescence. The compound's effects on cell viability and function should be assessed to ensure compatibility with cellular assays.

In vivo animal experiments with Cyanine5.5 amine are conducted for near-infrared fluorescence imaging. The dye or Cy5.5-labeled molecules are administered intravenously, intraperitoneally, or by other routes to animals. The animals are then imaged using a fluorescence imaging system with appropriate excitation and emission filters (Ex/Em ~648/710 nm). The fluorescence signal is analyzed to determine the distribution, targeting, and accumulation of the labeled molecules in tissues and organs. The dye's near-infrared fluorescence allows for deep tissue imaging with low background.

Dosing and administration of Cyanine5.5 amine for in vivo imaging depend on the specific application and the molecule being labeled. The dye is typically administered intravenously at doses of 1-10 nmol per mouse. The imaging is performed at various time points after administration to track the distribution of the labeled molecule. The dye's pharmacokinetics are characterized by its clearance from the blood and accumulation in target tissues. The compound is stored as a powder at -20°C, protected from light.

Specific toxicological data for Cyanine5.5 amine are not provided in the available sources. As a fluorescent dye, it is intended for research use only and is not for human consumption. Standard laboratory safety precautions should be followed when handling this compound, including the use of gloves and eye protection. The dye may cause irritation to skin, eyes, and respiratory tract upon contact. The compound's toxicity in vivo has not been extensively studied, but it is generally considered to be relatively low at the concentrations used for imaging.

[1]. Intracellular Uptake Mechanism of Bioorthogonally Conjugated Nanoparticles on Metabolically Engineered Mesenchymal Stem Cells. Bioconjug Chem. 2021 Jan 20;32(1):199-214.

[2]. Release kinetics of fluorescent dyes from PLGA nanoparticles in retinal blood vessels: In vivo monitoring and ex vivo localization. Eur J Pharm Biopharm. 2020 May;150:131-142.

Cyanine5.5 amine is a near-infrared (NIR) fluorescent dye belonging to the cyanine dye family. It has the molecular formula C46H58Cl2N4O. The dye exhibits strong fluorescence in the near-infrared region with excitation at 648 nm and emission at 710 nm. Cyanine5.5 amine is characterized by high sensitivity, photostability, and the ability to penetrate tissues for deep biological imaging studies. It is used in techniques such as fluorescence microscopy, flow cytometry, and in vivo imaging. The amine group allows for conjugation to biomolecules. The dye is used for labeling proteins, peptides, and other molecules. It is intended for research use only.

C46H58CL2N4O

753.8849

752.398

2097714-45-7

2097714-44-6 (without anion);2097714-45-7 (chloride);

165412490

Purple to purplish red solid powder

3

4

15

53

1290

0

[Cl-].[Cl-].O=C(CCCCCN1C2C=CC3=CC=CC=C3C=2C(C)(C)/C/1=C\C=C\C=C\C1C(C)(C)C2C3=CC=CC=C3C=CC=2[N+]=1C)NCCCCCC[NH3+]

KVJPEAWDFIBHDL-UHFFFAOYSA-N

InChI=1S/C46H56N4O.2ClH/c1-45(2)40(49(5)38-29-27-34-20-13-15-22-36(34)43(38)45)24-10-8-11-25-41-46(3,4)44-37-23-16-14-21-35(37)28-30-39(44)50(41)33-19-9-12-26-42(51)48-32-18-7-6-17-31-47;;/h8,10-11,13-16,20-25,27-30H,6-7,9,12,17-19,26,31-33,47H2,1-5H3;2*1H

N-(6-aminohexyl)-6-[(2E)-1,1-dimethyl-2-[(2E,4E)-5-(1,1,3-trimethylbenzo[e]indol-3-ium-2-yl)penta-2,4-dienylidene]benzo[e]indol-3-yl]hexanamide;chloride;hydrochloride

2934.99.9001

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.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~125 mg/mL (~165.81 mM)

Solubility in Formulation 1: 2.08 mg/mL (2.76 mM) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), suspension solution; with sonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 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.

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Solubility in Formulation 2: 2.08 mg/mL (2.76 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 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.

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 (Please use freshly prepared in vivo formulations for optimal results.)