Hi

If you are looking for ROS levels you may use certain ROS specific dyes such as DCFDA or Dihydroethidium or MitoSOX etc to find out the levels of ROS generated using fluocytometry/flurimertry or microscopy methods when you treat cells growing in vitro with gold/silver nano particles.  These methods will exactly tell you whether if at all ROS is being produced.

DCFDA will tell you cumulative cytosolic ROS where as MitoSOX is specific for mitochondrial superoxides. You may find numerous other dyes /kits specific for your experimental requirements.

GSH and other antioxidants like GST, CAT, SOD, GR, Gpx will be an indirect method to say whether ROS is involved as these enzymes will be associated with redox homeostasis. 

Best regards

Shubhankar

Vamsi, the best way for you as a student is to utilize the old method we all used/use, namely to search, now in the 21st century , the question on the Web. You got to go beyond the first bus-word you learned in the lab, GSH, and be more proactive to find the solutions. Perhaps a good way is to start with the question, what metabolic pathways control the redox state of erythrocytes. So there are compounds different from GSH, and there are enzymes involved in this process. Please use your brain. For example the advise given to you by Shubankar is not thought out, you have to look for a method that avoids the spectral interference by hemoglobin. The question is for you, what else can you do with the supernate you already collected and now assayed for GSH. There is an old lab manual out by "Beutler" that lists all metabolic tests you can do on red cells. I have it in my office, when I go in coming week, I will look for it.

I am looking to fear from your again.

Cheers

Dr.Lauf