Extraction and preconcentration of nickel, cadmium, cobalt, and lead cations using dispersive solid phase extraction performed in a narrow-bore tube

A new version of DSPE in a narrow-bore tube followed by HPLC-DAD was proposed for the analysis of Ni2+, Cd2+, Co2+, and Pb2+ cations. 2-Propanol is mixed with C18 sorbent and used for dispersing the sorbent into solution containing the cations oxinate complexes. The sorbent passes through the solution in a short time versus passing the solution from the cartridge which is done in the conventional SPE in a long time. In comparison to SPE, the active surface area is larger because of preventing sorbent clogging. EFs and LODs were obtained in the ranges of 831–1073 and 0.05–0.40 μg L−1, respectively.