protocol for metabolite estimation needed - (Dec/14/2006 )

can any one provide me the protocols for the estimation of ascorbate, hydrogen peroxide and glutathione spectrophotometrically.

VitC: a non-enzymatic, end point direct method is to mix with 2,4 dinitrophenylhydrazine. You get a red colour from hydrazone products. Measure at 520nm.

H202: (used in cholesterol and glucose assays and others) use an indirect enzymatic end point method: H202 + aminoantipyrine + Na 2-OH dichlorobenzenosulphonate with peroxidase forms a red quinonamine dye (read at 510nm).

Glutathione: use an indirect enzymatic end point method coupling glutathione reduction with NADPH. Glut + NADPH (acidic) with glut reductase -> NADP. Measure a drop in absorbance at 340nm.

Check out Tietz Clinical Chemistry for the details or let me know here.

catalase + h2o2, read at 240 nm

thanx for ur help and reply. it would be really nice and kind of u if u could send me some related research papers or any place from which i can get the complete protocol for estimation of these metabolites in details
thankin u in anticipation

thanx for ur help and reply. it would be really nice and kind of u if u could send me some related research papers on my email i.d shamsttt@gmail.com or any place from which i can get the complete protocol for estimation of these metabolites in details
thankin u in anticipation