Development of an Ozone-Assisted Sample Preparation Method for the Determination of Cu and Zn in Rice Samples

Table 1

Figures of merit for the OAE and MAE methods.

Parameter	Cu		Zn
	OAE	MAE	OAE	MAE
Linear range (µg L^−1)	Up to 5.0 mg L^−1		Up to 1.0 mg L^−1
LOD (mg kg^−1, n = 6)	0.20	0.18	0.08	0.10
LOQ (mg kg^−1, n = 6)	0.65	0.60	0.26	0.33
Precision (RSD%, OAE n = 18 and MAE n = 10)	3.0	3.1	2.9	3.3
Certified value (mg kg^−1) (NIST 1568a)	2.4 ± 0.3		19.4 ± 0.5
Obtained value (mg kg^−1)	2.41 ± 0.09	2.32 ± 0.06	18.6 ± 0.6	19.8 ± 0.7
Trueness (R%, OAE n = 18 and MAE n = 10)	100.4	96.7	95.9	102.1

Results are expressed as mean ± standard deviation. The replicate number arises from performing the OAE six times (3 simultaneous sample treatments each time plus a blank) considering the device design. Recovery (%) = (obtained value/certified value) × 100.