3.4. Calibration curve
The calibration curve used to determining cadmium with
GFAAS was made by measuring the series of working calibration
solution in which 2.50 gmL−1 lanthanum was added as
matrix modifier at optimum conditions (Fig. 1). Aswas shown in
Fig. 1, the linear ranges by optical temperature control and current
temperature control were 0–24 ngmL−1 and 0–15 ngmL−1,
respectively, both of the correlation coefficients were 0.9998,
which indicated that the linear range by optical temperature
control was wider than that by current temperature control.
Meanwhile, optical temperature control also could prolong the
life of graphite tube cuvette by 200–300%. So in this paper,
optical temperature control was selected to measure cadmium
in paint samples.