Hi, for some proteins their extinction coefficients will be different between the reduced and oxidized states. You may perform a wavelength scan for the protein solution under reducing and oxidizing conditions and at a certain wavelength the reduced form will show a peak and not the oxidized form (or vice versa).

Hi!! thanks so much!! but...how i can oxidize the protein beeing not so invasive? because Cu is so strong....oxygenated water is not so strong but is too....i'm sorry its my begining jajaja i'm inexpert!! the thing is....we want to see the redox state of some proteins because depending of their state can act on other proteins getting it active or inactive, and we want to see if this is the problem whom cause the inactivation of a dephosphorilation reaction to activate proteins involved in the reduction of ROS on cells.

Thanks so much!!!!!

Do you tried non-reducing / Reducing diagonal SDS PAGE?

Have a look at

Leichert and Jakob, Antioxid. Redox Signal. 8, 763-772

yeah i was thinking on a SDS-page and add it DTT who broke SH and other without DTT like control to see the differences between them...SH are when the protein is oxydated so...if the proteins are oxydated and i put DTT to broke SH...and i see diferences between the two samples...is because they are not so reduced... i dont know if i'm expresing well jajaj but i'm trying harder!! thank you all!!

You can perform it as well by saturation DIGE labelling. It is described here: Barjaktarovic Z, Schmaltz D, Shyla A, et al. Radiation–induced Signaling Results in Mitochondrial Impairment in Mouse

Heart at 4 Weeks after Exposure to X-rays. PLoS One 2011;6:e27811., chapter, Saturation DIGE labeling of oxidized mitochondrial proteins.

Good luck

thanks so much Zarko ^^