Nominal concentration (μg mL-1) Measured  concentration (Mean  ±  SD,  μg mL-1) Accuracy (RE, %) Precision (RSD, %) Recovery (%)
Intra-day        
0.4 0.43 ± 0.02 7.5 3.6 80.2
4.0 4.24 ± 0.06 6.0 1.3 84.6
10.0 9.47 ± 0.14 -5.3 1.4 86.4
Inter-day        
0.4 0.36 ± 0.02 -10 6.8 --
4.0 4.18 ± 0.33 4.2 8.0 --
10.0 10.62 ± 0.78 6.2 7.3 --
Table 1: Intra- and inter-day accuracy and precision (n=6).