|
چکیده
|
Lead ion is considered one of the toxic heavy metals and is concentrated in aquatic ecosystems and poses a serious hazard to human health, even at trace levels [1]. Numerous diseases are related to Pb(II), such as respiratory, anemia, cardiovascular and endocrine systems[2]. The maximum allowable level of lead in drinking waters by the US Environmental Protection Agency (EPA) and the European Union (EU) are respectively 15 ppb and 10 ppb. So, the determination of Pb(II) in water sources is necessary. Owing to the low concentration of Pb(II) in real samples and complex matrices, a preconcentration and purification step is necessary before instrumental detection. Various methods have been used for the extraction and preconcentration of Pb(II). Microextraction in a packed syringe (MEPS) is a new technique for miniaturized SPE that was introduced by Abdel-Rehim in 2004 [3]. This method's advantages include high extraction efficiency, low consumption of organic solvents, and convenience of operation. Generally, sorbent plays an important role in selectivity and sensitivity. In this study, the silica particles were modified with 3- Mercaptopropyltrimethoxysilan (MPTS) as a sorbent for microextraction in a packed syringe (MEPS) of Pb(II) from aqueous solutions. The lead ions were eluted using 500 μL HCl 0.5 M and analyzed via graphite furnace atomic absorption spectroscopy. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray energy diffraction (EDX) spectroscopy methods were used to characterize the obtained sorbent. Under optimal experimental conditions, the method had a linear range of 0.01–50 μg/L.
|