Evaluation of the copper(II) reduction assay using bathocuproinedisulfonic acid disodium salt for the total antioxidant capacity assessment: The CUPRAC–BCS assay

Acquisition of dietary copper: a role for anion transporters in intestinal apical copper uptake

“…Although previous studies suggest strongly that hCTR1 transports Cu(I), it is not known whether Cu(I) or Cu(II) is involved in the chloridedependent pathway that we observe. Spectrophotometric measurements utilizing bathocuproine disulfate (10) showed that 1 mM ascorbate reduces all of the Cu(II) chloride used in our transport assays (1-10 M) to Cu(I), without changing the pH of the transport medium (data not shown). The reducing agent ascorbate had no significant effect on copper uptake in the salt medium at pH 7.4 (Fig.…”

Physical features, phenolic compounds, betalains and total antioxidant capacity of coloured quinoa seeds (Chenopodium quinoa Willd.) from Peruvian Altiplano

“…A modified direct QUENCHER-CUPRAC procedure was used to perform total antioxidant capacity of coloured quinoa samples (Campos, Guzmán, López-Fernández, & Casado, 2009;Tufan, Çelik, Özyürek, Güçlü, & Apak, 2013). Briefly, 2 mg of the sample was put on each tube and reacted with 950 lL of 0.25 mM BCS (dissolved in 10 mM phosphate buffer, pH 7.4/ethanol 1:1 v/v -PPE-), 50 lL PPE, and 250 lL 0.5 mM CuSO 4 (dissolved in PPE) under shaking on a ''movil rod'' shaker at maximum speed for 30 min (room temperature).…”

A novel hydrogen peroxide scavenging assay of phenolics and flavonoids using cupric reducing antioxidant capacity (CUPRAC) methodology

“…The CUPRAC method of antioxidant measurement, introduced by our research group to world literature (Apak et al, 2004(Apak et al, , 2007, is based on the absorbance measurement of the CUPRAC chromophore, Cu(I)-neocuproine (Nc) chelate, formed as a result of the redox reaction of antioxidants with the CUPRAC reagent, Cu(II)-neocuproine (Nc: 2,9-dimethyl-1,10-phenanthroline), where absorbance is recorded at the maximal light absorption wavelength of 450 nm. In this respect, Campos et al (2009) developed a similar spectrophotometric method using bathocuproinedisulfonic acid disodium salt (BCS) as the chelating agent for Cu(I) emerging from the reaction of Cu(II) with antioxidants (i.e. the cupric ion reducing capacity -BCS assay, not competent with conventional CUPRAC in regard to kinetics and response to lipophilic antioxidants) for the total antioxidant capacity (TAC) assessment in human plasma and urine.…”