General description

For spectrophotometric measurement of viable cells. Absorbance of converted dye is measured at a wavelength of 540 nm.

Application

In Vitro Toxicology Assay Kit, Neutral Red based has been used:

to measure the lysosomal enzyme activity in HB8902 cells
to study the cell viability of human alveolar epithelial cells
to study the cell viability in fibroblasts

Biochem/physiol Actions

Neutral red (NR) is a red dye that accumulates in the lysosome by actively transferring across the cell membranes. The dye is extracted and the uptake is quantitated by spectroscopy. The NR uptake assay is the most commonly used cytotoxicity test. It is widely applicable in environmental and biomedical studies to estimate the number of viable cells in culture. The NR dye in vitro tissue culture studies is used in assessing viral cytopathogenicity and detection of toxic compounds.