One-Step Tunel Assay Kits

TUNEL staining is used to detect apoptosis in cells and tissues. The TUNEL assay uses a fluorescent dye that binds to DNA fragments released from apoptotic cells, which makes them detectable under a microscope. The TUNEL apoptosis kit is a valuable tool for researchers, as it can help them to understand the process of apoptosis in detail, and to identify genes that are important for apoptosis. The TUNEL apoptosis kit is also used in cancer research, to determine whether tumors are apoptotic or necrotic.

Advantages of One-Step TUNEL Assay Kits

One-Step TUNEL assay kits are easier to use than the traditional two-step assay. These kits use a single buffer and enzyme mix, so there is no need to prepare two separate reactions. The One-Step TUNEL assay kit is particularly useful for detecting apoptosis in situ, or in fixed cells or tissues. The advantages of One-Step TUNEL assay kits are as follows

  • Multiple Choices: FITC, AF488, AF594, EV450, AF647, AF555
  • Quick & Simple Protocol: One-step method, with the dewaxing process is achieved with only one step
  • Safe and Non-Toxic: Contains potassium cacodylate (dimethylarsinic acid)
  • Cost Effective

Assay Genie One-Step TUNEL Apoptosis Product Kits

Product Name Ex/EM (nm) Detection Method


Fluorometric Method


Fluorometric Method


Fluorometric Method


Fluorometric Method


Fluorometric Method


Colorimetric Method

Types of TUNEL Assay Kits

The most popular TUNEL reagents on the market are generally divided into two categories: fluorescent TUNEL kits (for fluorescence microscopy or flow cytometry) and HRP-DAB TUNEL assays (for light microscopy). Therefore, the choice of TUNEL kits depends on the the equipment available. Choose fluorescent TUNEL products if a fluorescence microscope is accessible, and a HRP-DAB TUNEL assay kit if a light microscope is accessible. Compared to HRP-DAB TUNEL test kits, fluorescent TUNEL tests are more beneficial as they are simple to use and have a relatively quicker experiment time. The results are also easy to observe in the case of fluorescent TUNEL assays.

Choosing the Right TUNEL Kit

Assay Genie offers a wide range of one-step fluorescent TUNEL assay kits, so how to make the right choice for experiments?

Firstly, this requires a knowledge about the fluorescence microscope's settings, especially the excitation and emission wavelength spectra. UV light excites DAPI, which emits blue light. Blue light excites AF488 and FITC, which emit green light. Green light excites AF594 and AF555, which emit red light.

Fluorescein Excitation wavelength (Ex) Emission wavelength (Em)




















The second factor to be taken into consideration is whether the sample has auto-fluorescence, the following guidelines must be adhered to while choosing the appropriate TUNEL kit.

a) If the test sample either does not show fluorescence or contains red fluorescence, the One-Step TUNEL Assay Kit (Green, FITC) or the One-Step TUNEL Assay Kit (Green, AF488) are recommended.

Note : The anti-quenching function of AF488 is superior than that of FITC, so if you need to view the green fluorescence of the sample for a longer period of time, use the AF488 kit.

b) If the experimental sample exhibits green fluorescence, use the TUNEL Assay Kit (Red, AF594) or One-Step TUNEL Assay Kit (Red, AF555).

c) If both red and green fluorescence are observed in the experimental sample, the One-Step TUNEL Assay Kit (Red, AF647) is recommended.

Note: AF647 has rather stringent requirements for fluorescence instruments, therefore confocal microscopes would provide more accurate results.