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.