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NovaBlock™ Solution

Highest performance solution created to block non-specific binding of PE-tandem dyes as well as NovaFluor labels.

Application note: NovaBlockTM requires no change to most flow cytometry staining protocols. Prior to staining, in addition to other blocking solutions, add 5 µL of NovaBlockTM per 1×106 cells and incubate on ice for 5 minutes.



NovaBlock™ Solution has been specifically formulated to block the non-specific binding of NovaFluor labels, PE and APC tandems (PE-Dazzle™ 594, PE-Cy5, PE-Cy7, APC-Cy7 and APC-Fire™ 750) observed with macrophages and monocytes.

This non-antibody, non-protein based blocking solution has been shown to act as a high performing blocking solution for flow cytometry in stopping the non-specific binding of NovaFluor labels as well as cyanine-based PE and APC tandems.

Monocytes and background are a thing of the past.

  • Use interchangeably for PE, APC tandems and NovaFluor™ staining in flow cytometry.
  • Incorporates seamlessly into your current flow cytometry protocol with no additional steps.
  • Better resolve populations by combining with NovaFluors to combine the spectrally cleanest fluorescent labels with industry-leading background reduction. 
  • Can be used without NovaFluor™ labels as well as a high performance replacement to your current monocyte blocking solution.
Overlay dot plots displaying human PBMC CD3 and CD14 expression following no block (yellow), NovaBlockTM (blue), and BioLegend® True-Stain Mononcyte BlockerTM (red). Data was assessed on an Attune NxTTM.

Consistently amazing discovery with these Blocking Solution features:

Incorporates into current staining workflow with zero additional hands-on time
Specially optimized blocking solution for flow cytometry applications
Engineered to enable high resolution biology


Blocking Solutions

Blocking SolutionFormulationPurposeSpecies CompatibilityNotes
NovaBlockTMNon-antibody & non-proteinBlocks non-specific binding of NovaFluorsTM, tandem dyes, and PE/Dazzle 594TM to monocytes/macrophages.Human & MouseCan be used in addition to Fc block. Formulated as 5 µL/test. Does not impact compensation beads.
True-Stain Monocyte BlockerTMNon-antibodyBlocks non-specific binding of tandem dyes and PE/Dazzle 594TM to monocytes/macrophages.Human & Mouse 
Human Fc BlockHuman IgGBlocks non-specific binding of antibodies to Fc receptors expressed on monocytes/macrophages, granulocytes, B cells, and dendritic cells.HumanNot recommended for staining human IgG.
Mouse Fc Block Anti-mouse CD16/CD32 antibody /Anti-mouse 2.4G2 antibodyBlocks non-specific binding of antibodies to Fc receptors expressed on monocytes/macrophages, granulocytes, B cells, and dendritic cells.Mouse
Irrelevant ProteinBSA/FCS/FBS/human serum/mouse serum/rat serum Blocks non-specific binding of antibodies to Fc receptors expressed on monocytes/macrophages, granulocytes, B cells, and dendritic cells.Human & mouse 
BD HorizonTM Brilliant Stain Buffer (or BD HorizonTM Brilliant Stain Buffer Plus)Unreported proprietary formulationReduces dye-dye interactions between different polymer dyes.Human & MouseFormulated as 50 µL/test (or 10 µL/test). May impact fluorescence of compensation beads.
eBioscienceTM Super Bright Staining BufferUnreported proprietary formulationReduces dye-dye interactions between different polymer dyes.Human & MouseFormulated as 5 µL/test. Not compatible with  UltraComp eBeadsTM.

NovaBlockTM Compatibility 

True-Stain Monocyte BlockerTM 
Human TruStain FcXTM
TruStain FcXTM
Irrelevant Protein
BD HorizonTM Brilliant Stain Buffer
eBioscienceTM Super Bright Staining Buffer
IgG Staining
DNA Intercalating DyesX
Amine Reactive Dyes
Compensation Beads

Reduce background from Cyanine-based dyes and NovaFluor™ labels

Performance-tested block solutions serve as the best answer for reducing background observed from monocytes and macrophages binding non-specifically to cyanine-based fluorescent dyes.

Overlay histogram display of lymphocyte (A) and monocyte (B) CD4 expression assessed by NovaYellowTM 660 anti-human CD4 combined with NovaBlockTM (cyan), no block (orange), and unstained cells (white) in a single stain flow cytometry experiment performed on healthy thawed human peripheral blood mononuclear cells (PBMCs). Data was acquired on an Attune NxTTM (Blue/Red/Yellow/Violet).

Cell Phenotyping by Flow Cytometry

Uncover and better resolve cell population heterogeneity by flow cytometry. In combination with our NovaBlock, NovaFluor labels increase the parameters accessible per cell on extant instrumentation, and enable you to discover more.


(NovaBlockTM, NovaFluorTM, and NovaYellowTM are registered trademarks of Phitonex Inc. BioLegend®, PE-DazzleTM, and True-Stain Monocyte BlockerTM are registered trademarks of BioLegend, Inc. BD HorizonTM is a registered trademark of Becton, Dickinson and Company. AttuneTM, eBioscienceTM and UltraComp eBeadsTM are registered trademarks of Thermo Fisher Scientific. CyTM is a trademark of GE Healthcare.)