logo
AAT Bioquest

mFluor™ UV455 SE

mFluor™ dyes are developed for multicolor flow cytometry-focused applications. These dyes have large Stokes Shifts, and can be well excited by the laser lines of flow cytometers (e.g., 350 nm, 405 nm, 488 nm and 633 nm). mFluor™ UV dyes are optimized to be excited with a UV laser at 350 nm. AAT Bioquest offers the largest collection of fluorescent dyes that are excited by UV laser at 350 nm. mFluor™ UV 455 dyes have fluorescence excitation and emission maxima of ~350 nm and ~455 nm respectively. These spectral characteristics make them a unique color for flow cytometry application. mFluor™ UV 455 SE is reasonably stable and shows good reactivity and selectivity with protein amino groups. mFluor™ UV 455 SE provides a convenient tool to label monoclonal, polyclonal antibodies or other proteins (>10 kDa) for flow cytometric applications with the UV laser excitation.

Example protocol

PREPARATION OF STOCK SOLUTIONS

Unless otherwise noted, all unused stock solutions should be divided into single-use aliquots and stored at -20 °C after preparation. Avoid repeated freeze-thaw cycles.

1. Protein stock solution (Solution A)
Mix 100 µL of a reaction buffer (e.g., 1 M  sodium carbonate solution or 1 M phosphate buffer with pH ~9.0) with 900 µL of the target protein solution (e.g. antibody, protein concentration >2 mg/mL if possible) to give 1 mL protein labeling stock solution.
Note     The pH of the protein solution (Solution A) should be 8.5 ± 0.5. If the pH of the protein solution is lower than 8.0, adjust the pH to the range of 8.0-9.0 using 1 M  sodium bicarbonate solution or 1 M pH 9.0 phosphate buffer.
Note     The protein should be dissolved in 1X phosphate buffered saline (PBS), pH 7.2-7.4. If the protein is dissolved in Tris or glycine buffer, it must be dialyzed against 1X PBS, pH 7.2-7.4, to remove free amines or ammonium salts (such as ammonium sulfate and ammonium acetate) that are widely used for protein precipitation.
Note     Impure antibodies or antibodies stabilized with bovine serum albumin (BSA) or gelatin will not be labeled well. The presence of sodium azide or thimerosal might also interfere with the conjugation reaction. Sodium azide or thimerosal can be removed by dialysis or spin column for optimal labeling results.
Note     The conjugation efficiency is significantly reduced if the protein concentration is less than 2 mg/mL. For optimal labeling efficiency the final protein concentration range of 2-10 mg/mL is recommended.


2. mFluor™ UV455 SE stock solution (Solution B)
Add anhydrous DMSO into the vial of mFluor™ UV455 SE to make a 10 mM stock solution. Mix well by pipetting or vortex.
Note     Prepare the dye stock solution (Solution B) before starting the conjugation. Use promptly. Extended storage of the dye stock solution may reduce the dye activity. Solution B can be stored in freezer for two weeks when kept from light and moisture. Avoid freeze-thaw cycles.

SAMPLE EXPERIMENTAL PROTOCOL

This labeling protocol was developed for the conjugate of Goat anti-mouse IgG with mFluor™ UV455 SE. You might need further optimization for your particular proteins.
Note     Each protein requires distinct dye/protein ratio, which also depends on the properties of dyes. Over labeling of a protein could detrimentally affects its binding affinity while the protein conjugates of low dye/protein ratio gives reduced sensitivity.


Run conjugation reaction
  1. Use 10:1 molar ratio of Solution B (dye)/Solution A (protein) as the starting point:  Add 5 µL of the dye stock solution (Solution B, assuming the dye stock solution is 10 mM) into the vial of the protein solution (95 µL of Solution A) with effective shaking. The concentration of the protein is ~0.05 mM assuming the protein concentration is 10 mg/mL and the molecular weight of the protein is ~200KD.
    Note     We recommend to use 10:1 molar ratio of Solution B (dye)/Solution A (protein). If it is too less or too high, determine the optimal dye/protein ratio at 5:1, 15:1 and 20:1 respectively.
  2. Continue to rotate or shake the reaction mixture at room temperature for 30-60 minutes. 

Purify the conjugation
The following protocol is an example of dye-protein conjugate purification by using a Sephadex G-25 column.
  1. Prepare Sephadex G-25 column according to the manufacture instruction.
  2. Load the reaction mixture (From "Run conjugation reaction") to the top of the Sephadex G-25 column.
  3. Add PBS (pH 7.2-7.4) as soon as the sample runs just below the top resin surface.
  4. Add more PBS (pH 7.2-7.4) to the desired sample to complete the column purification. Combine the fractions that contain the desired dye-protein conjugate.
    Note     For immediate use, the dye-protein conjugate need be diluted with staining buffer, and aliquoted for multiple uses.
    Note     For longer term storage, dye-protein conjugate solution need be concentrated or freeze dried. 

Spectrum

Product family

NameExcitation (nm)Emission (nm)Extinction coefficient (cm -1 M -1)Quantum yieldCorrection Factor (260 nm)Correction Factor (280 nm)
mFluor™ UV375 SE3513873000010.9410.0990.138
mFluor™ UV460 SE3584561500010.8610.350.134
mFluor™ UV420 SE353421750001---
mFluor™ UV520 SE503524800001-0.4950.518
mFluor™ UV540 SE5425609000010.3510.6340.463
mFluor™ UV610 SE5906099000010.250.9490.904

References

View all 3 references: Citation Explorer
Deep ultraviolet lasers for flow cytometry.
Authors: Telford, William and Georges, Thierry and Miller, Clint and Voluer, Pascal
Journal: Cytometry. Part A : the journal of the International Society for Analytical Cytology (2019): 227-233
Ultraviolet 320 nm laser excitation for flow cytometry.
Authors: Telford, William and Stickland, Lynn and Koschorreck, Marco
Journal: Cytometry. Part A : the journal of the International Society for Analytical Cytology (2017): 314-325
Near-ultraviolet laser diodes for brilliant ultraviolet fluorophore excitation.
Authors: Telford, William G
Journal: Cytometry. Part A : the journal of the International Society for Analytical Cytology (2015): 1127-37
Page updated on October 4, 2024

Ordering information

Price
Unit size
Catalog Number1642
Quantity
Add to cart

Additional ordering information

Telephone1-800-990-8053
Fax1-800-609-2943
Emailsales@aatbio.com
InternationalSee distributors
Bulk requestInquire
Custom sizeInquire
Technical SupportContact us
Purchase orderSend to sales@aatbio.com
ShippingStandard overnight for United States, inquire for international
Request quotation

Physical properties

Molecular weight

729.68

Solvent

DMSO

Spectral properties

Absorbance (nm)

359

Correction Factor (260 nm)

0.651

Correction Factor (280 nm)

0.406

Extinction coefficient (cm -1 M -1)

200001

Excitation (nm)

357

Emission (nm)

461

Quantum yield

0.421

Storage, safety and handling

H-phraseH303, H313, H333
Hazard symbolXN
Intended useResearch Use Only (RUO)
R-phraseR20, R21, R22

Storage

Freeze (< -15 °C); Minimize light exposure
UNSPSC12171501
<strong>Top)</strong>&nbsp;Spectral pattern was generated using a 4-laser spectral cytometer. Spatially offset lasers (355 nm, 405 nm, 488 nm, and 640 nm) were used to generate four distinct emission profiles, then, when combined, yielded the overall spectral signature.&nbsp;<strong>Bottom)</strong>&nbsp;Flow cytometry analysis of whole blood cells stained with CD4-mFluor&trade; UV455 conjugate. The fluorescence signal was monitored using an Aurora spectral flow cytometer in the mFluor&trade; UV455 specific UV5-A channel.
<strong>Top)</strong>&nbsp;Spectral pattern was generated using a 4-laser spectral cytometer. Spatially offset lasers (355 nm, 405 nm, 488 nm, and 640 nm) were used to generate four distinct emission profiles, then, when combined, yielded the overall spectral signature.&nbsp;<strong>Bottom)</strong>&nbsp;Flow cytometry analysis of whole blood cells stained with CD4-mFluor&trade; UV455 conjugate. The fluorescence signal was monitored using an Aurora spectral flow cytometer in the mFluor&trade; UV455 specific UV5-A channel.
<strong>Top)</strong>&nbsp;Spectral pattern was generated using a 4-laser spectral cytometer. Spatially offset lasers (355 nm, 405 nm, 488 nm, and 640 nm) were used to generate four distinct emission profiles, then, when combined, yielded the overall spectral signature.&nbsp;<strong>Bottom)</strong>&nbsp;Flow cytometry analysis of whole blood cells stained with CD4-mFluor&trade; UV455 conjugate. The fluorescence signal was monitored using an Aurora spectral flow cytometer in the mFluor&trade; UV455 specific UV5-A channel.
Fluorescent dye NHS esters (or succinimidyl esters) are the most popular tool for conjugating dyes to a peptide, protein, antibody, amino-modified oligonucleotide, or nucleic acid. NHS esters react readily with the primary amines (R-NH<sub>2</sub>) of proteins, amine-modified oligonucleotides, and other amine-containing molecules. The resulting dye conjugates are quite stable.