پديدآورندگان :
Shams Alireza - Ferdowsi University of Mashhad, Mashhad, Iran , Ashraf Narges ashraf-n@um.ac.ir Ferdowsi University of Mashhad, Mashhad, Iran , Arbab-Zavar Mohammad Hossein - Ferdowsi University of Mashhad, Mashhad, Iran , Masrournia Mahboobeh - Mashhad Branch, Islamic Azad University, Mashhad, Iran.
چكيده فارسي :
Palladium is an element which seems to be biologically inactive. However, many of its compounds show cytotoxic effects on humans beings including liver and kidney damage, asthma, allergies, and various other health problems [1]. Palladium is widely used in dental and medicinal purposes, jeweleries, electronics and industrial catalytic applications [2]. Therefore, development of methods enabling the direct determination of palladium is of paramount importance [3]. Herine, a novel simple and sensitive method has been reported for determination of palladium in real samples. The method is based on electrochemical hydride generation followed by in-situ trapping of the volatile species on the graphite tube surface and detection of palladium by electrothermal atomic absorption spectrometry. Electrochemical hydride generation of palladium is performed in the cathodic chamber of an electrochemical cell using an efficient cathode material, namely, tungsten-inert gas welding electrodes. Palladium hydrides are transferred by the flow of argon gas to the graphite tube where they trapped and preconcentrated. Then, the trapped species are atomized and detected using electrothermal atomic absorption spectrometry. To optimize the performance of the proposed method, the effects of several effective experimental parameters such as graphite tube modifier, argon gas flow rate, trapping temperature, atomizing temperature, type and concentration of catholyte, and also electrolysis duration were investigated and optimize using central composite optimization design and the response surface equations. Under optimum operating conditions, the calibration curve was plotted within the concentration range of 0.05 to 10 ng mL-1 of Pd(II). The dynamic range was obtained to be within the range of 0.1 to 5 ng mL-1 of Pd(II). Also, the limit of detection (LOD, 3sb/m) and the limit of quantification (LOQ, 10sb/m) of the method for Pd(II) was achieved to be 0.08 ng mL-1 and 2.5 ng mL-1, respectively. The relative standard deviation (RSD%) of the propose method was 3.5% for 5 replicate measurements. The influence of the potential chemical interferences was also studied. The proposed method was simple, fast, cost efficient, and sensitive for determination of palladium in many real samples.
