Disposable nickel screen-printed sensor based on dimethylglyoxime-containing carbon ink

Disposable complexing (preconcentrating) sensor strips for trace nickel have been fabricated by doping the screen-printed carbon ink with ligand dimethylglyoxime (DMG). The carbon ink is shown to be a useful matrix for incorporating the DMG, with the ligand maintaining its attractive coordination chemistry following the printing and firing processes. The response is characterized with respect to the ink composition, preconcentration period and potential, solution conditions and other variables. A short (30 s) accumulation period yields a detection limit of 5 mu g/L nickel. The highly stable response indicates great promise for use as reusable devices. Measurement of nickel in a river water sample is demonstrated. Such incorporation of ligands into screen-printed carbon inks provides a promising route for thick-film sensors based on the preconcentration/voltammetric strategy.