A synthesized ternary polymer composite and its use for SPE of trace metals in Coffee, tea and legumes

A new synthesized ternary polymer composite, polystyrene/polyacrylonitrile/polyindole (PSt/PAN/PIN), was used as an adsorbent. The structure of synthesized composite was supported by FTIR, BET, X-RD, TGA, SEM and AFM technique. A SPE method with synthesized composite was developed for the preconcentration of chromium, copper, iron, manganese, lead and zinc ions. The adsorption capacity were found in the range of 37.4-56.7 mg g^-1. Under the best conditions, the preconcentration factor of method was found as 100. Relative standard deviation was found at ≤ 3.3% (n = 11). The detection limits of analytes were obtained as: 0.9 μg L^-1 for Cr(III), 1.2 μg L^-1 for Cu(II), 2.0 μg L^-1 for Fe(III), 1.4 μg L^-1 for Mn(II), 0.9 μg L^-1 for Pb(II) and 2.0 µg L^-1 for Zn(II). Firstly, this SPE method was applied to certified reference material, and than coffee, tea, legumes. The trace metals was analyzed by flame atomic absorption spectrometry.