Amperometric flow injection analysis as a new approach for studying disperse systems (original) (raw)

2009, Electrochimica Acta

Fast and simple quantitative determination in dispersed systems (layered double hydroxides -LDHssuspensions in aqueous solutions) was performed by a procedure that couples flow injection and amperometric detection (FI-AM). LDH dispersions are injected in a continuous flow (1 mL min −1 ) of 0.05 mol L −1 KNO 3 solution and [Cu(H 2 O) 6 ] 2+ , used as a probe, is detected at a glassy carbon electrode housed in a flat electrochemical cell. The current intensity, recorded at the selected working potential (−0.25 V vs Ag/AgCl/NaCl (3 mol L −1 )), presents a linear relationship with [Cu(H 2 O) 6 ] 2+ concentration and the procedure offers high sensitivity (slope = 0.036 A/(mol L −1 )), a low detection limit (=0.7 mol L −1 ) and a wide quantification range (4-200 mol L −1 ).