“…Separation and pre-concentration procedures such as Liquid-Liquid Extraction (LLE), Solid Phase Extraction (SPE) and Homogenous Liquid-Liquid Extraction (HLLE) make it feasible to determine the trace of metal cations such as Mg 2+ , Ca 2+ , Cr 3+ , Mn 2+ , Fe 3+ , Co 2+ , Co 3+ , Ni 2+ , Cu 2+ , Zn 2+ , Se 2+ , Mo 6+ , Ru 4+ , Rh 3+ , Pd 2+ , Ag + , Cd 2+ , Sn 2+ , Te 2+ , Te 4+ , Hg 2+ and Pb 2+ in natural samples using molecular beam mass spectrometry with tunable Vacuum Ultraviolet (VUV) synchrotron radiation ( Figure 1) and various analytical methods . Preconcentration methods generally improve sensitivity and selectivity of the analysis with the additional advantage of isolation the analyte from the interfering compounds [22,23]. In the recent years, Homogenous Liquid-Liquid Extraction (HLLE) using molecular beam mass spectrometry with tunable Vacuum Ultraviolet (VUV) synchrotron radiation and various analytical methods has been extensively used in sample preparation due to speed, suitable performance, higher concentration factor and less solvent consumption in comparison with Liquid-Liquid Extraction (LLE) and Solid Phase Extraction (SPE) .…”