Table 1: Influence of the FIA system variables: multivariate design.

ExperimentFlow rate HCl (mL min−1)Flow rate NaBH4 (mL min−1)Mixing coil length (cm)Absorbance Se(IV) 50 μg · L−1 dissolution ( )

11.31.71500.044
22.93.61500.069
33.54.5500.076
41.31.71000.047
52.93.61000.069
62.22.81000.062
73.54.51000.072