Determination of Copper, Nickel and Cobalt in Water and Food Samples by Faas after Separation and Preconcentration Using Multiwalled Carbon Nanotubes Modified by Methyl-(2-pyridyl) Ketone Oxime

A solid phase extraction (SPE) procedure was presented for the preconcentration of copper, nickel and cobalt using multiwalled carbon nanotubes (MWCNTs) modified by methyl-(2-pyridyl) ketone oxime (MPKO, as a new complexing agent) as a solid sorbent prior to their determination by flame atomic absorption spectroscopy (FAAS). Some analytical parameters including pH, sample volume, concentration of MPKO and adsorbent, elution conditions such as volume and concentration of eluent, flow rate of solution and matrix ions, were optimized. At optimum conditions, the detection limits (3 SDb/m) of 0.18, 0.28, and 0.47 μg L for Cu(II), Ni(II), and Co(II) along with preconcentration factors of 90 respectively, were obtained. The method has been successfully applied for the determination of the aforementioned ions in food and water samples.