Screen-printed electrodes for nitrite based on anion-exchanger-doped carbon inks

Abstract
Disposable voltammetric sensors for nitrite have been microfabricated by screen-printing an anion-exchanger (Aliquat 336)-modified carbon ink. The modifier ability to accumulate low levels of nitrite is not compromised by the screen-printing and low-temperature drying processes. Experimental variables influencing the preconcentration/voltammetric performance are elucidated and optimized. A short (30 s) accumulation period yields a detection limit of 30 µg l–1 nitrite. Monitoring of micromolar levels of nitrite in drinking- and groundwater samples is illustrated. Prospects of mass production of other preconcentrating modified electrodes are discussed.