Polypyrrole nanowire modified with Gly-Gly-His tripeptide for electrochemical detection of copper ion

Functionalized polypyrrole nanotube arrays as electrochemical biosensor for the determination of copper ions

“…The walls thickness of the PPy NT arrays is ca. 60-70 nm, and the carboxylation of PPy NT arrays to give rise to PPy-COOH NT arrays rarely affects the morphological features since neither the overall NT structure nor the apparent diameter of the NT changed [5]. The morphology of the PPy NT arrays is of cauliflower shape, similar as that of the final PPy-COOH NT arrays.…”

“…The stripping method using chemically modified electrode has higher selectivity due to the selective affinity of the tripeptide GGH modifier to capture Cu 2+ [26,40]. In addition, its small size is ideal for locating the peptide probe to the transducer in close proximity which facilitating the PPy-GGH nanoarray electrode to detect Cu 2+ in a selective manner [5].…”

“…Following the capture step, the modified electrode was transferred into a copper ion-free buffer (50 mM ammonium acetate, 50 mM NaCl, pH 7.0) for detection of Cu 2+ where the captured metal ions on the electrode surface were reduced before recording the stripping current using SWV [41]. The overoxidized PPy could avoid its large background current that may hinder an accurate determination of a SWV peak current arising from oxidation of Cu 0 in the polymer matrix [5]. As illustrated in Fig.…”

“…Especially, the functionalized CP nanowires (NW) and nanotubes (NT) are predicted to be excellent sensing materials relating with their features of high surface areas, porous structure, abundant surface functionalities, and sensitive electron transduction [4]. Among the CP nanomaterials, PPy nanomaterials are very attractive substrates for immobilization of biomaterials, rendering their wide utilization for the design and construction of various biosensors harnessing immobilized enzymes, and covalently attached ligands or specific biological species [5][6][7][8].…”

“…Lee and co-workers reported a copper ions (Cu 2+ ) biosensor based on an overoxidized PPy NW layer. The overoxidized PPy NW layer was formed by one step pyrrole electropolymerization in the presence of sodium carbonate [5]. A biosensor based on enzyme functionalized poly(pyrrole-3-carboxylic acid) NTs which were immobilized onto a microelectrode substrate via covalent linkages was developed by Jang and co-workers [3].…”