Product No. 11465015001
The non-radioactive, colorimetric assay system using XTT (sodium 3´-[1- (phenylaminocarbonyl)- 3,4- tetrazolium]-bis (4-methoxy6-nitro) benzene sulfonic acid hydrate) was first described by Scudiero, P.A. et al. 1, 2 and improved in subsequent years by several other investigators 3, 4. The XTT assay is used to measure cellular metabolic activity as an indicator of cell viability, proliferation and cytotoxicity. This colorimetric assay is based on the reduction of a yellow tetrazolium salt (sodium 3´-[1- (phenylaminocarbonyl)- 3,4- tetrazolium]-bis (4-methoxy6-nitro) benzene sulfonic acid hydrate or XTT) to an orange formazan dye by metabolically active cells (fig. 1) 5. The formazan dye formed is soluble in aqueous solutions and is directly quantified using a scanning multiwell spectrophotometer (ELISA reader). An increase in number of living cells results in an increase in the overall activity of mitochondrial dehydrogenases in the sample. This increase directly correlates to the amount of orange formazan formed, as monitored by the absorbance (see fig. 2).
It is used for the measurement of cell proliferation in response to growth factors, cytokines and nutrients (see fig. 2). It is also used for the measurement of cytotoxicity, like the quantification of tumor necrosis factor α- or β- effects (see fig. 3) or the assessment of cytotoxic or growth inhibiting agents such as inhibitory antibodies.
Figure 1.Metabolism of XTT to a water-soluble orange colored formazan salt by viable cells. Schematic of an XTT assay plate.
Catalog No. 11465015001
XTT Reagent
Electron-coupling reagent
Preparation of XTT labeling mixture
For the determination of human interleukin-6 (hIL-6) activity on 7TD1 cells (mouse-mouse hybridoma, DSMZ, ACC 23) (see fig. 2).
Additional reagents required:
Protocol:
Figure 2.Proliferation of 7TD1 cells (mouse-mouse hybridoma) in response to recombinant human interleukin-6 (hIL-6) using XTT assay.
To determine the cytotoxic effects of human tumor necrosis factor-α (hTNF-α, T6674) on WEHI-164 cells (mouse fibrosarcoma, 87022501) (see fig. 3).
Additional reagents required:
Protocol:
Figure 3.Determination of the cytotoxic activity of recombinant human TNF-α (hTNF-α) on WEHI-164 cells (mouse fibrosarcoma) using XTT assay
MTT assay and WST-1 assay can also be used for measuring cell viability and proliferation.
To continue reading please sign in or create an account.
Don't Have An Account?