Poly(etheretherketone)-turnings a novel sorbent material for lead determination by flow injection flame atomic absorption spectrometry and factorial design optimization

A novel hydrophobic sorbent material for on-line column preconcentration and separation systems coupled with atomic spectrometry was developed. Poly(etheretherketone) (PEEK) in the form of turnings was used as packing material and evaluated for trace lead determination in environmental samples. Sample and ammonium diethyl-dithiophosphate (DDPA) reagent were mixed on-line and the Pb(II)-DDPA complex was retained effectively on PEEK-turnings. Isobutyl methyl ketone (IBMK) was adopted for efficient analyte complex elution and subsequently transportation into the nebulizer-burner system for atomization. The developed sorbent material has shown, excellent chemical and mechanical resistance, fast adsorption kinetics permitting the use of high sample flow rates without significant loss of retention efficiency. For 120 s sample preconcentration time the sampling frequency was 20 h⁻¹, the enhancement factor was 110, the detection limit (3 s) was c_L = 0.32 μg L⁻¹, and the relative standard deviation (RSD) was s_R = 2.2%, at the 50.0 μg L⁻¹ Pb(II) level. The accuracy of the developed method was evaluated by analyzing certified reference materials.