This work describes the development of a solid phase spectrophotometry method in a mSI-LOV system
for cadmium, zinc, and copper determination in freshwaters. NTA (Nitrilotriacetic acid) beads with 60
e160 mm diameter were packed in the flow cell of the LOV for a mSPE column of 1 cm length. The
spectrophotometric determination is based on the colourimetric reaction between dithizone and the
target metals, previously retained on NTA resin. The absorbance of the coloured product formed is
measured, at 550 nm, on the surface of the NTA resin beads in a solid phase spectrophotometry
approach