Catalog # Availability Size / Price Qty
FNIR-Tag, NHS | CAS No. 2365033-54-9 | Fluorescent Dyes
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Description: Near-infrared fluorescent dye for labeling of amines; supplied as NHS ester

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%

Product Details

Biological Activity

FNIR-Tag, NHS is a near-infrared fluorescent dye; supplied as an NHS ester for coupling to primary amine groups. FNIR-Tag, NHS allows a higher degree of labeling (DOL) with less aggregation than leading competitor product. When conjugated to antibodies, FNIR-Tag, NHS exhibits 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/emission maxima = 766/788 nm; Extinction coefficient = 200,000 M-1cm-1; QY = 0.099.

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

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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Technical Data

Soluble to 10 mM in DMSO and to 10 mM in DMF
Store at -20°C

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.

Additional Information

Licensing Caveats:
Sold under license from the National Institute of Health

Product Datasheets

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