A voltammetric peptide biosensor for Cu metal ion quantification in coffee seeds.

A prion-derived copper(II)-binding peptide was assembled onto a gold electrode for the building of a voltammetric biosensor for measuring the Cu metal ion in biological samples. The chosen sequence was H-CVNITKQHTVTTTT-NH, with an appended cysteine residue for binding to the gold surface as a self-assembled monolayer and a histidine residue as the anchorage point for copper(II) complexation. The biosensor showed a linear range of 10 to 10 M with an 8.

Toxic metals (Pb and Cd) and their respective antagonists (Ca and Zn) in infant formulas and milk marketed in Brasilia, Brazil.

In non-ideal scenarios involving partial or non-breastfeeding, cow's milk-based dairy products are mainstream in infant feeding. Therefore, it is important to study the concentrations of potentially neurotoxic contaminants (Pb and Cd) and their respective counteracting elements (Ca and Zn) in infant dairy products. Fifty-five brands of infant formulas and milk sold in Brasilia, Brazil were analyzed.

Ca(II) -gamma-thionin complex: interaction studies by differential pulse voltammetry and MALDI-TOF/MS.

In this work we investigated the formation of a complex between gamma-thionin SI alpha1 and Ca(2+) using differential pulse voltammetry and MALDI TOF/MS. A stoichiometry rate of one calcium ion per one SI alpha1 molecule was obtained. K(d) values of 1.