Pyridine-2,6-diamine-functionalized Fe₃O₄ nanoparticles as a novel sorbent for determination of lead and cadmium ions in cosmetic samples.

A novel sorbent based on pyridine-2,6-diamine-functionalized Fe(3)O(4) nanoparticles was developed and characterized by X-ray powder diffraction (XRD), elemental analysis, IR spectroscopy and scanning electron microscopy (SEM). The application of the sorbent was investigated for pre-concentration and determination of lead and cadmium ions in aqueous samples. Effects of various factors such as the sample pH, eluent parameters (type, concentration and volume) and time (adsorption and desorption) were appraised. The effects of several interfering ions on method recovery were also investigated. The limit of detection (LOD) was found to be 1.3 and 0.089 μg L(-1) for lead and cadmium ions, respectively. Recovery and precision (RSD%) of the method were above 97.9% and below 0.6%, respectively. Validation of the outlined method was performed by analysing several certified reference materials. This method was successfully used for determination of lead and cadmium ions in several cosmetic samples, which are usually contaminated by lead and cadmium ions.