Dear Rohit, If your protein has a spectroscopic signature corresponding to the different redox states, you could try using single crystal spectroscopy (e.g. UV-visible) to validate the redox state before and after data collection.
Best wishes, Mike On 5 Jan 2018, at 10:45, rohit kumar <rohit...@gmail.com<mailto:rohit...@gmail.com>> wrote: Dear All, I am solving a structure (resolution 2 A) of an enzyme having Iron as a metal cofactor. How could I know oxidising state of the bound Iron (Fe+2 or Fe+3)? Thank you in advance -- WITH REGARDS Dr. Rohit Kumar Singh