LDH-Cytotoxicity Colorimetric Assay Kit II

Cells treatment with the cytotoxic compound may undergo necrosis, in which they lose membrane integrity. Hence cytotoxicity can be detected by the quantification of plasma membrane damage. Lactate dehydrogenase (LDH) is a stable enzyme exists in nearly all living cells. When damage of the plasma membrane, LDH is rapidly released into the cell culture supernatant.

 The LDH-Cytotoxicity Colorimetric Assay Kit II provides a simple and fast way for the quantification of cytotoxicity based on the measurement of activity of LDH released from damaged cells, which can be detected by a coupled enzymatic reaction: LDH oxidizes lactate to produce NADH, which then reacts with WST to generate yellow color, which can be easily detected by plate reader or spectrophotometer at OD450 nm. The intensity of the yellow color correlates directly with the cell number lysed. Since WST is more stable, the reaction can be read multiple times and stopped at any time point during the reaction. Since WST is brighter, the assay needs less amount of culture medium and thus significantly reduced the background from culture medium and serum. In this assay, cells can be cultured in regular 10% serum containing medium without special medium or reducing serum is required. The kit also provides LDH positive control. Assay takes less than 1 hour.