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TUNEL Assay Apoptosis Detection Kit

The CF® dye TUNEL Assay Apoptosis Detection Kit label apoptotic cells in fixed tissue sections or cellular samples for fluorescence microscopy or flow cytometry.

Product Attributes

Apoptosis/viability marker

DNA fragmentation

For live or fixed cells

For fixed cells/tissue sections

Detection method/readout

Fluorescence microscopy, Flow cytometry

Assay type/options

Endpoint assay

Fixation options

Permeabilize before staining, Fix before staining (methanol), Fix before staining (formaldehyde)


Green, Red, Far-red

Product origin

TdT enzyme (calf thymus); recombinant, produced in E. coli

Storage Conditions

Store at -10 to -35 °C, Protect from light

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Note: Due to operating restrictions related to our COVID-19 response, primary antibody conjugates of R-PE, APC, PerCP, HRP, or AP are temporarily unavailable. All other antibody options are still available. We apologize for the inconvenience. Please see our easy-to-use Mix-n-Stain™ Antibody Labeling Kits for labeling antibodies with R-PE, APC, tandem dyes, and enzymes.
Catalog #
50 reactions
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Product Description

These kits use enzymatic labeling of DNA double-strand breaks for fluorescence staining of apoptotic cells in fixed samples or tissue sections by TUNEL.


  • Direct labeling of DNA ds breaks with fluorescent dUTP
  • Bright & photostable next-generation CF® dyes
  • For fixed cells or tissue sections
  • Detect by fluorescence microscopy or flow cytometry

Kit Components

  • Equilibration Buffer
  • CF® Dye TUNEL Reaction Buffer
  • TdT Enzyme (calf thymus; recombinant, produced in E. coli)

Note: Kits include reagents for 50 reactions using 50 uL per reaction.

In TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling), TdT enzyme catalyzes the addition of labeled dUTP to the 3′- ends of the internucleosomal DNA strand breaks that are a hallmark of apoptosis. The CF® dye TUNEL Assay Apoptosis Detection Kits employs dUTP conjugated to the exceptionally bright and photostable fluorescent dyes, for single step fluorescent TUNEL labeling of fixed cells or tissues for analysis by fluorescence microscopy or flow cytometry. Learn more about Biotium’s next-generation CF® Dyes.

See our full selection of Cell Viability & Apoptosis Kits.

CF® Dye TUNEL Assay Apoptosis Detection Kits

DyeEx/EmSizeCatalog No.
CF®488A490/515 nm50 reactions30063
CF®594593/614 nm50 reactions30064
CF®640R642/662 nm50 reactions30074
Kit sized based on 50 uL reaction volume.



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