Influence of the electrografting method on the performances of a flow electrochemical sensor using modified electrodes for trace analysis of copper (II).

International audienceThe performances of carboxylate- and cyclam-modified graphite felt electrodes prepd. by different electrografting methods for trace anal. of copper (II) were compared to det. the influence of the immobilization process of the linkers on the sensor properties. The derivatization performed by cathodic redn. of diazonium salts and by anodic oxidn. of amines in org. and aq. media was first evaluated by cyclic voltammetry and XPS analyses, showing a higher surface coverage for the redn. process. Cyclam was subsequently attached on the COOH-modified graphite felts by a coupling reaction. The modified electrodes were then employed in a flow anal. system for trace anal. of copper (II) ions. The influence of the surface coverage and the nature of the linker on the electrochem. signal obtained by linear sweep stripping voltammetry anal. after a preconcn. step performed at open circuit was highlighted. The selectivity estd. in the presence of lead used as a common ion interferent was higher when a selective receptor was used and depends on the nature of the linker. [on SciFinder(R)