Disposable voltammetric sensors for nitrite have been microfabricated
by screen-printing an anion-exchanger (Aliquat 336)-modified carbon in
k. The modifier ability to accumulate low levels of nitrite is not com
promised by the screen-printing and low-temperature drying processes.
Experimental variables influencing the preconcentration/voltammetric p
erformance are elucidated and optimized. A short (30 s) accumulation p
eriod yields a detection limit of 30 mu g 1(-1) nitrite. Monitoring of
micromolar levels of nitrite in drinking- and groundwater samples is
illustrated. Prospects of mass production of other preconcentrating mo
dified electrodes are discussed.