demonstrate that with these reagent concentrations and
two, 2-mL reaction coils, the NaR method quantitatively
reduced nitrate to nitrite over the entire calibration range
and produced results comparable to those obtained with the
cadmium reduction method. Complete reduction of nitrate
to nitrite by the NaR method was not achieved when the
experiment was repeated with a single 2-mL reaction coil
(see Table 2). When the concentration of NaR in the mixed
enzyme reagent was doubled, quantitative reduction of
nitrate to nitrite was achieved using one 2-mL reaction coil,
but this approach was not pursued because it would have
increased per-test costs associated with the NaR reduction
method.