Observation and measurement of cell viability and proliferation is a crucial aspect of many cell-based applications, including cellular imaging, cell culture, functional screening, and drug discovery. Because cellular biology is inherently complex and can be investigated via various parameters, there are similarly many types of cell-based tests and assays. These include assays for live/dead cells, cytotoxicity, apoptosis, mitochondrial membrane potential, reactive oxygen species. Activity of key enzymes involved in cell health can also be tested, such as caspases and dehydrogenases. Use the filters on the left to help narrow down the search for the right cell viability assay.
A caspase is a type of protease that when activated cleaves protein substrates. This leads to the cell becoming disassembled, showing signs of the beginning stages of apoptosis, or programmed cell death. Therefore, this makes caspases an ideal biomarker to use to detect apoptosis. The most common caspase assays come in kits and use fluorometric, colorimetric, or flow cytometry-based methods. These assays are typically used with other cell death assays to gain a complete picture.