Spectraviewer image of Brilliant Violet 421 dye

Brilliant Violet™ dyes, including Brilliant Violet™ 421 (BV421), are a polymer dye-based technology and compatible with both spectral flow cytometry, as well as traditional flow cytometry. The violet laser has unique channels far from heavily occupied detectors allowing for larger panels.

BV421 is excited by the 405 nm violet laser and emits at 421 nm. This dye has a medium-to-high relative brightness and can be used for cell surface, intracellular, and nuclear staining.

When using two or more Super Bright, Brilliant Violet, Brilliant Ultra Violet™, or other polymer dye- conjugated antibodies in a staining panel, we recommend that you use Super Bright Complete Staining Buffer (Cat. No. SB-4401-42) or Brilliant Stain Buffer (Cat. No. 00-4409-42) to minimize any non- specific polymer interactions.

BV421 dye dashboard

Initial brightness

The violet laser-excitable BV421 dye is optimized for use both cell surface and intracellular flow applications. Can be used for spectral flow cytometry applications. 

Photostability in buffer


Laser line


Excitation max

Emission max


BV421 dye products

We offer BV421 dye conjugated to primary antibodies for use in flow cytometry.

Antibody conjugates

Brilliant Stain Buffer
Super Bright Staining Buffer

Experimental data using BV421 dye products

Figure 1. Excitation and emission of Brilliant Violet™ 421 dye (BV421).

Figure 2. Spectral signature of BV421 dye. Data acquired on a 5-laser Cytek Aurora and normal human peripheral blood cells stained with clone RPA-T8 (hCD8) conjugated to BV421 dye (Cat. No. 404-0088-42) were used for analysis.

Dot plot of TNF-alpha-BV421 vs CD4-FITC in unstimulated and stimulated cells

Figure 3. Normal human peripheral blood cells were unstimulated (left) or stimulated for 5 hours with the Cell Stimulation Cocktail (plus protein transport inhibitors) (Cat. No. 00-4975-03) (right). Cells were then stained intracellularly, using the Intracellular Fixation & Permeabilization Buffer Set (Cat. No. 88-8824-00) and protocol, with CD4 Monoclonal Antibody, FITC (Cat. No. 11-0049-42) and TNF alpha Monoclonal Antibody, Brilliant Violet™ 421 dye (Cat. No. 404-7321-82). Viable cells in the lymphocyte gate were used for analysis, as determined by Fixable Viability Dye eFluor™ 780 dye (Cat. No. 65-0865-18).

Dot plot of samples stained with IgG2a control vs CD3e-FITC and CD4-BV421 vs CD3e-FITC

Figure 4. C57BL/6 mouse splenocytes were stained with CD3e Monoclonal Antibody, FITC (Cat. No. 11-0031-82) and 0.06 µg of Rat IgG2a kappa Isotype Control, Brilliant Violet™ 421 dye (Cat. No. 404-4321-81) (left) or 0.06 µg of CD4 Monoclonal Antibody, Brilliant Violet™ 421 dye (right) (Cat. No. 404-0042-82). Viable cells in the lymphocyte gate were used for analysis, as determined by 7-AAD (Cat. No. 00-6993-50).

Not for resale. Super Bright Polymer Dyes are sold under license from Becton, Dickinson and Company.

Brilliant Ultra Violet™ and Brilliant Violet™ are trademarks or registered trademarks of Becton, Dickinson and Company or its affiliates, and is used under license.

For Research Use Only. Not for use in diagnostic procedures.