Downscaling a multicommuted flow injection analysis system for the photometric determination of iodate in table salt

Abstract

In this work a downscaled multicommuted flow injection analysis setup for photometric determination is described. The setup consists of a flow system module and a LED based photometer, with a total internal volume of about 170 μL. The system was tested by developing an analytical procedure for the photometric determination of iodate in table salt using N,N-diethyl-henylenediamine (DPD) as the chromogenic reagent. Accuracy was accessed by applying the paired t-test between results obtained using the proposed procedure and a reference method, and no significant difference at the 95% confidence level was observed. Other profitable features, such as a low reagent consumption of 7.3 μg DPD per determination; a linear response ranging from 0.1 up to 3.0 m IO 3 −, a relative standard deviation of 0.9% ( n = 11) for samples containing 0.5 m IO 3 −, a detection limit of 17 μg L −1 IO 3 −, a sampling throughput of 117 determination per hour, and a waste generation 600 μL per determination, were also achieved.