2.3. Sequential injection procedure
The analytical cycle for the determination of Sn is summarized in
Table 1. It began with the sequential aspiration of 25L of DMSO,
150L of sample and 25L of HQSA to the holding coil. Then by
flow reversal the aspirated zones were propelled to the fluorimetric
detector at a flow rate of 3 mL min−1 and an analytical signal was
obtained at approximately 15 s.