Measurement of total antioxidant capacity of human plasma: Setting and validation of the CUPRAC-BCS method on routine apparatus ADVIA 2400

作者：Gosmaro Fabio^*; Bagnati Marco; Berto Silvia; Bellomo Giorgio; Prenesti Enrico

来源：Talanta, 2013, 115: 526-532.

DOI：10.1016/j.talanta.2013.06.015

• Total antioxidant capacity
• Oxidative stress
• Human plasma
• Method validation

Background: Quantification of Total Antioxidant Capacity (TAC) of human plasma is an important clinical target, since many diseases are suspected to be related with oxidative stress. The CUPRAC-BCS (BCS =Bathocuproinedisulfonic acid) method was chosen since it works using the photometric principle, with stable and inexpensive reagents and at physiological pH. %26lt;br%26gt;Methods: The method is based on the complex equilibria between Cu(II)-BCS (reagent) and Cu(I)-BCS. Cu (I)-BCS complex is formed by reducing ability of the plasma redox active substances. The photometric signal is achieved at 478 nm and calibration is performed using urate as a reference substance. %26lt;br%26gt;Results: Linearity, linear working range, sensitivity, precision, LoD, LoQ selectivity and robustness have been considered to validate the method. Absorbance at 478 nm was found linear from 0.0025 up to 2.0 mmol L-1 of urate reference solution. Precision was evaluated as within-day repeatability, S-r=4 mu mol L-1, and intermediate-precision, S-I(T)=15 mu mol L-1. LoD and LoQ resulted equal to 7.0 mu mol L-1 and 21 mu mol L-1 respectively while robustness was tested having care for pH variation during PBS buffer preparation. Tests on plasma (80 samples) and on human cerebrospinal fluid (30 samples) were conducted and discussed. %26lt;br%26gt;Conclusions: By the analytical point of view, the photometric method was found to be simple, rapid, widely linear and reliable for the routine analysis of a clinical laboratory. By the clinical point of view, the method response is suitable for the study of chemical plasma quantities related to redox reactivity.

• 出版日期2013-10-15