Pricing Availability   Qty
Description: Near-infrared (NIR) fluorescent dye (Reactive group: NHS ester) optimized for in vivo imaging
Chemical Name: 2-((E)-2-((E)-2-(3-((4-((2,5-dioxopyrrolidin-1-yl)oxy)-4-oxobutyl)dimethylammonio)propoxy)-3-(2-((E)-1-(2-(2-(2-methoxyethoxy)ethoxy)ethyl)-3,3-dimethyl-5-sulfonatoindolin-2-ylidene)ethylidene)cyclohex-1-en-1-yl)vinyl)-1-(2-(2-(2-methoxyethoxy)ethoxy)ethyl)-3,3-dimethyl-3H-indol-1-ium-5-sulfonate
Purity: ≥70% (HPLC)
Protocols (1)
Literature (1)

Biological Activity for FNIR-Tag, NHS

Key information: FNIR-Tag, NHS is a near-infrared fluorescent dye; supplied with an NHS ester reactive group for the labeling of primary amines with a high degree of labeling (DOL).

Application: Designed for in vivo imaging. Also suitable for flow cytometry.

Properties and Photophysical Data: FNIR-Tag, NHS provides a higher degree of labeling (DOL) with less aggregation than a leading competitor product when used for antibody conjugation. FNIR-Tag, NHS - antibody conjugates exhibit reduced liver uptake in vivo compared with leading competitor conjugates. In addition, FNIR-Tag, NHS conjugates are significantly brighter than leading competitor conjugates at similar labeling densities in vivo and in vitro. Antibody conjugation efficiency is greatest at pH 7.4. Excitation and emission maxima (λ) are 766 nM and 788 nM, respectively; quantum yield = 0.099; extinction coefficient = 200,000 M-1cm-1; A280 correction factor = 0.05.

For further information about how FNIR-Tag, NHS may be used, please see our protocol: Conjugation Protocol for Amine Reactive Dyes.

Scientific Data

Flow Cytometry Flow cytometry data of FNIR-Tag, NHS in mouse endothelial cells View Larger

Application of FNIR-Tag, NHS in vitro. C166 mouse endothelial cells were incubated with 20 nM virus-like particles (VLPs) at 37 °C for 1 h. Samples were extensively washed to remove VLPs not bound to the cellular surface and subsequently fixed to preserve any interactions prior to analysis by flow cytometry. FNIR-Tag conjugates (red) were significantly brighter than IR-800CW conjugates (black) at similar labeling at low (A) and high (B) fluorophore loadings. For more information on this work read Luciano et al (2019) A nonaggregating heptamethine cyanine for building brighter labeled biomolecules. ACS Chem.Biol. 14 934 PMID: 31030512

In vivo Imaging in vivo fluorescent images of FNIR-Tag, NHS and competitor in mouse post-injection View Larger

Application of FNIR-Tag, NHS in vivo. (A) Representative images demonstrating detection of virus-like particle (VLP) conjugates in the liver at 2 h (left panel) and 24 h (right panel) post injection. Scale bar represents epifluorescent in total radiant efficiency. (B) Quantitative analysis of the fluorescence intensity detected at 2 and 24 h post injection. Data are mean value ± standard error. Statistical analysis was performed between groups at the same time point using Student’s t-test. *p ≤ 0.05; **p ≤ 0.01. For more information on this work read Luciano et al (2019) A nonaggregating heptamethine cyanine for building brighter labeled biomolecules. ACS Chem.Biol. 14 934 PMID: 31030512

Licensing Information

Sold under license from the National Institute of Health

Optical Data for FNIR-Tag, NHS

FNIR-Tag, NHS Dye Spectra
Emission Color Near-IR
λabs 765 nm
λem 788 nm
Extinction Coefficient (ε) 200,000 M-1cm-1
Quantum Yield (φ) 0.099
Closest Laser line 750 nm
Reactive Group NHS ester
Reactivity Primary amines
Correction Factor 280 0.05
Application Flow Cytometry, In Vivo Imaging

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Use our spectra viewer to interactively plan your experiments, assessing multiplexing options. View the excitation and emission spectra for our fluorescent dye range and other commonly used dyes.

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Technical Data for FNIR-Tag, NHS

M. Wt 1157.4
Formula C57H80N4O17S2
Storage Store at -20°C
Purity ≥70% (HPLC)
CAS Number 2365033-54-9
Smiles [O-]S(=O)(C1=CC=C2[N+](CCOCCOCCOC)=C(C(C)(C2=C1)C)/C=C/C3=C(/C(CCC3)=C/C=C4C(C)(C5=CC(S([O-])(=O)=O)=CC=C5N\4CCOCCOCCOC)C)OCCC[N+](CCCC(ON6C(CCC6=O)=O)=O)(C)C)=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 for FNIR-Tag, NHS

Solvent Max Conc. mg/mL Max Conc. mM
DMSO 11.57 10
DMF 11.57 10

Preparing Stock Solutions for FNIR-Tag, NHS

The following data is based on the product molecular weight 1157.4. 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.

Select a batch to recalculate based on the batch molecular weight:
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
0.1 mM 8.64 mL 43.2 mL 86.4 mL
0.5 mM 1.73 mL 8.64 mL 17.28 mL
1 mM 0.86 mL 4.32 mL 8.64 mL
5 mM 0.17 mL 0.86 mL 1.73 mL

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Product Datasheets for FNIR-Tag, NHS

References for FNIR-Tag, NHS

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

Luciano et al (2019) A nonaggregating heptamethine cyanine for building brighter labeled biomolecules. ACS Chem.Biol. 14 934 PMID: 31030512

If you know of a relevant reference for FNIR-Tag, NHS, please let us know.

Keywords: FNIR-Tag, NHS, FNIR-Tag, NHS supplier, near, infrared, fluorescent, dye, fluorescence, imaging, flow, cytometry, amine, labeling, labelling, NHS, ester, Cyanine, Dyes, (Cy, Dyes), Near, Infrared, (NIR), Fluorescent, 7373, Tocris Bioscience

Citations for FNIR-Tag, NHS

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Protocols for FNIR-Tag, NHS

The following protocol features additional information for the use of FNIR-Tag, NHS (Cat. No. 7373).

Literature in this Area

Tocris offers the following scientific literature in this area to showcase our products. We invite you to request* your copy today!

*Please note that Tocris will only send literature to established scientific business / institute addresses.

Fluorescent Dyes and Probes Research Product Guide

Fluorescent Dyes and Probes Research Product Guide

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