9^th Biotechnology Congress

Biography

Biography: Rita Ferin

Abstract

Ascorbic (AA) and uric (UA) acids act as antioxidants and are capable to react with biologically relevant oxidants. Therefore, these compounds can be considered important oxidative stress plasma markers. We aimed to developed a simple, rapid, sensitive, and accurate ion-exclusion HPLC-UV methodology (isocratic elution) for the simultaneously determination of AA and UA in human plasma, as well as its employment in the assessment of the antioxidant status in a group of Azorean subjects. Pre-analytical procedures were required for an accurate and reliable measurement such the use of heparin as anticoagulant and the addition of meta-phosphoric acid to plasma samples before storage. Chromatographic separation was achieved by an isocratic elution on a HEMA-BIO 1000 SB analytical column (250 x 4.6 mm I.D., 10 m) using a phosphate buffer, pH 2.4, as a mobile phase. Results indicated an excellent linearity with correlation coefficients (r2) ≥0.999. The LOQ of the AA and UA was 1.02 and 1.42 nmol/mL, respectively, while LOD ranged from 0.306 to 0.426 nmol/mL. A great repeatability for both antioxidants was found where the CV (%) values for intra-day were lower than 1.8% and under 6.5% for the inter-day assay. For AA the recovery ranged from 92% to 96% and for UA from 99% to 100%. This validated method allows the determination of both antioxidants within 10 min, and is well suited to routine measurements and/or high-throughput clinical analysis. The methodology was applied to assess the antioxidant status of a group of Azorean subjects.