Thioredoxin Reductase Activity Colorimetric Assay Kit

Thioredoxin reductase (TrxR) is an ubiquitous enzyme that mediates various cellular processes (e.g. p53 activity, cell growth and defense of oxidative damage). The mammalian TrxR downregulate non-disulfide substrates such as lipoic acids, selenite and hydrogen peroxide etc. Thioredoxin Reductase Assay Kit offers a fast and easy colorimetric assay for measuring TrxR activity in different sample. In this assay, TrxR catalyzes the reduction of 5, 5’-dithiobis (2-nitrobenzoic) acid (DTNB) with NADPH to 5-thio-2-nitrobenzoic acid (TNB2-), produce an intense yellow color (λmax = 412 nm). Because glutathione peroxidase and glutathione reductase can also reduce DtNB in crude biological ample, TrxR specific inhibitor is used to detect the TrxR specific activity. Two assays are carried out: the first measurement is of the total DTNB reduction by the sample, and the second one is the DTNB reduction by the sample with the TrxR specific inhibitor. The DTNB reduction by TrxR is the difference between the two results.