LDH Cytotoxicity Assay Kit

Lactate Dehydrogenase (LDH) is an intracellular enzyme widely present in the cytoplasm of cells and is involved in the reversible conversion between lactate and pyruvate during glycolysis. When the plasma membrane is damaged, LDH is rapidly released into the cell culture supernatant, which is a key feature of cells undergoing apoptosis, necrosis and other forms of cellular damage. Therefore, the activity level of LDH in the supernatant can be used as an important biomarker for assessing cell membrane integrity and cytotoxicity, and is widely used in studies of drug toxicology, cell viability, and immune cell killing.
This kit is based on the LDH-catalysed conversion of lactate to pyruvate, accompanied by the reduction of NAD⁺ to NADH, followed by the further reaction of NADH with INT to produce the orange-red compound formazan. Formazan has a high absorbance value at 490 nm and is directly proportional to LDH activity. Therefore, by measuring the absorbance, LDH activity can be quantitatively detected, thus indirectly reflecting the degree of cell damage or apoptosis.