Elabscience Total Oxidant Status (TOS) Colorimetric Assay Kit

Detection principle 
Under acid conditions, the oxidizing material in the sample can oxidizeFe2+toFe 3+ , which binds highly with xylenol orange to produce a blue-purplecomplex.When the pH of solution is in the range of 2-3, its maximumabsorptionwavelength is around 590 nm, and the color depth is proportional tothecontentofoxidation substances in a certain concentration and a certain time, soastoindirectly calculate the total oxidation state of the sample.

Sample preparation 
Serum and plasma: detect directly. If not detected on the same day, theserumorplasma can be stored at -80℃ for a month. 

Tissue sample: 
Harvest the amount of tissue needed for each assay (initial recommendation20mg). 
Wash tissue in cold PBS (0.01 M, pH 7.4). 
Homogenize 20 mg tissue in 180 PBS (0.01 M, pH7.4) withadouncehomogenizer at 4℃. 
Centrifuge at 10000×g for 10 min at 4℃to remove insoluble material. Collectsupernatant and keep it on ice for detection. 
Meanwhile, determine the protein concentration of supernatant(E-BC-K318-M).

Calculation 
The standard curve: 
1. Average the duplicate reading for each standard. 
2. Subtract the mean ∆A value of the blank (Standard # ①) fromall standardreadings. This is the absoluted ∆A value. 
3. Plot the standard curve by using absoluted ∆A value of standardandcorrespondent concentration as y-axis and x-axis respectively. Create thestandardcurve (y = ax + b) with graph software (or EXCEL).