The small volumes of the samples were injected from a funnel or hemisphere-shape cup made from a hydrophobic PTFE plate. Various researches [25] and [26] have studied this micro-injection technique of discrete samples, proving that the nebulization of a 100 μL sample gives the same sensitivity as the one obtained by conventional nebulization. Others [27] reported that using even a 60 μL volume of a sample the maximum sensitivity can be achieved with a better precision than 1.5 RSD%. The peak height of the analytical signal depends on the injected volume, the wetting of the surface of the sampling vessel and the nebulizer capillary by the liquid sample as well as the solution flow rate of the nebulizer.