2.2 Biochemistry analysis
2.2.1 Peroxide assay. The peroxide content was determined in plasma by means of a quantitative colorimetric assay, according to the kit indications ”QuantiChromTM Peroxide Assay Kit (DIOX-250) - BioAssay Systems”, at the end of the process the optical density at 570 nm was quantified in ELISA plate reading equipment (Chromate), reporting values ​​of ng/ml.
2.2.2 Nitric oxide assay. The nitric oxide content was determined in plasma by means of a quantitative colorimetric assay, according to the kit indications ”QuantiChromTM Nitric Oxide Assay Kit (D2NO-100) - BioAssay Systems”, at the end of the process the optical density was quantified at 570 nm, in an ELISA plate reading equipment (Chromate), reporting in µM values.
2.2.3 Oxidized proteins assay. Protein carbonyl content in plasma was determined as previously described.12 The plasma was incubated with DNPH (2,4-Dinitrophenylhydrazine; 10 mM) and HCl (2N) and finally with guanidine hydrochloride (6M). Assessment of carbonyl formation was done on the basis of formation of protein hydrazone by reaction with DNPH. The absorbance was measured at 370 nm. Result was expressed as nmol carbonyl per mg protein.