Using the experimental conditions identified in the optimization
step, the method allowed the determination of cadmium in
vinegar with a characteristic mass of 1.2 pg, being, the limits of
detection (LOD) and quantification (LOQ) of 4 and 14 ng L1
,
respectively, for a sample volume of 20.0 lL. These limits were
determined as being LOD = (3r/s) and LOQ = (10r/s), where (r) is
the standard deviation for the measurements from the blank
solutions and (s) is the slope of the external calibration curve.
The precision (expressed as relative standard deviation) varied
from 1.07% to 2.33% as can be seen in Table 5.