Nanostructured materials as sorbents for sample preparation in trace metal analysis

Abstract: Trace metals pollution of the environment is a global challenge. This is because these may be a health risk to humans, as well as other living organisms. Metals such as As, Co, Cr, Cd, Pb, Tl, Te, Sb, are regarded as toxic inorganic pollutants. These metals normally exist at trace levels in various environmental matrices such as, soil, water and biological samples to name a few. Toxic metals can cause severe health problems that can even lead to fatalities for animals and human beings, this is due to the fact that unlike organic contaminants these trace toxic metal ions are non-biodegradable and have a tendency to accumulate in vital human organs, such as liver, lungs, heart and kidneys. Therefore, the aim of this research was to prepare a nanostructured material and applied as an effective adsorbent for preconcentration of trace from complex matrices. The quantification of the trace metals was achieved using inductively coupled plasma optical emission spectrometry (ICP-OES) technique. The nanocomposites were then characterized using scanning electron microscopy (SEM), Fourier Transform infrared (FTIR) spectroscopy transmission electron microscopy (TEM), and x-ray diffraction (XRD). Several effective experimental parameters controlling the preconcentration of the trace metals were optimized using central composite design. Under optimum conditions they showed good the linearity ranged, correlation of coefficients (R2), limits of detection (LODs) and quantification (LOQs). The prepared adsorbents are Mg/Al-LDH@CNTs nanocomposite, MPC@SiO2@Fe3O4, and Fe3O4@Mg/Al-layered double hydroxide were characterized and used to develop three preconcentration methods which are mainly ultrasound assisted solid phase extraction using magnetic and dispersive ultrasound-assisted cloud point- dispersive μ-solid phase extraction...Ph.D. (Chemistry