Cytoselect Cell Viability and Cytotoxicity Assay Assay Kit

Principle of the assay: CytoSelect Cell Viability and Cytotoxicity Assay Kit provides a colorimetric and fluorometric format for measuring and monitoring cell viability. The kit contains MTT reagent, Calcein AM, and Ethidium Homodimer. Detergent and Lysis Buffer are provided for extracting the MTT reagent or the Calcein AM/EthD-1 from cell samples. Saponin, a cell death initiator, is also included as a control. The kit is suitable for use with light and fluorescence microscopes, colorimetric and fluorometric multiwell plate scanners, flow cytometers, and other colorimetric or fluorometric detection systems. The kit contains sufficient reagents for the evaluation of 96 assays in a 96-well plate, or 24 assays in a 24-well plate. Cells can then be treated with compounds or agents that affect viability. Live cells are detected with the MTT reagent as well as the Calcein AM. Dead cells are detected with the EthD-1 reagent. Finally, cell viability/cytotoxicity is determined using the colorimetric and fluorometric detection reagents. An increase in cell viability is accompanied by cell growth, while a decrease in cell viability can indicate the toxic effects of compounds or suboptimal culture conditions. The assay principles are basic and can be applied to most eukaryotic cell lines, including adherent and non-adherent cells and certain tissues. The kit does not react with bacteria or yeast.

Background: The measurement and monitoring of cell viability is an essential technique in any laboratory focused on cell-based research. This skill allows for the optimization of cell culture conditions as well as the determination of cytokine, growth factor, or hormone activity. More importantly, the cytostatic nature of anticancer compounds in toxicology testing, the efficacy of therapeutic chemicals in drug screening, and cell-mediated cytotoxicity can all be assessed through the quantification and monitoring of cell viability and growth. Cell viability characteristics include cellular metabolic activity and cell membrane integrity. One method for measuring metabolic activity is to incubate the cells with a tetrazolium salt such as MTT, which is cleaved into a colored formazan product by metabolically active cells. The green fluorescent viability dye Calcein AM can measure intracellular esterase activity, which is another indicator of cell viability. Live cells can convert the nonfluorescent, cell-permeable polyanionic calcein acetoxymethyl (Calcein AM) dye to the highly fluorescent calcein. The cleaved calcein remains in the cells. Ethidium homodimer (EthD-1) is an excellent marker for measuring dead cells. EthD-1 is a red fluorescent dye that can only penetrate damaged cell membranes. EthD-1 will fluoresce with a 40-fold enhancement upon binding ssDNA, dsDNA, RNA, oligonucleotides, and triplex DNA. Background fluorescence levels are very low because the dyes are virtually non-fluorescent before interacting with cells. This method of detection is more efficient, safer, less expensive, and a more sensitive method for determining cell viability or cytotoxicity compared to traditional viability assays such as 51Cr release or trypan blue exclusion.

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Small volumes of CytoSelect Cell Viability and Cytotoxicity Assay assay kit vial(s) may occasionally become entrapped in the seal of the product vial during shipment and storage. If necessary, briefly centrifuge the vial on a tabletop centrifuge to dislodge any liquid in the container`s cap. Certain products may require to ship with dry ice and additional dry ice fee may apply.

MBS168166 is an assay kit targeting CytoSelect Cell Viability and Cytotoxicity Assay.