Determination of trace Cd, Cu, Fe, Pb and Zn in diesel and gasoline by inductively coupled plasma mass spectrometry after sample clean up with hollow fiber solid phase microextraction system

•Hollow fiber solid phase microextraction of metal ions in diesel and gasoline•Use of hollow fiber-supported sol–gel combined with cation exchange resin•Optimization of HF-SPME using multivariate techniques•Determination of Cd, Cu, Fe, Pb and Zn using ICP–MS•Relatively low LOD and LOQ

This study reports a simple and efficient method for the determination of trace Cd, Cu, Fe, Pb and Zn in diesel and gasoline samples by inductively coupled plasma mass spectrometry after matrix removal and analyte pre-concentration using hollow fiber-solid phase microextraction (HF–SPME). The optimization of HF-SPME procedure was carried out using two-level full factorial and central composite designs. Four factors (variables), that are, sample solution pH, acceptor phase amount, extraction time and eluent concentration were optimized. Under the optimized experimental conditions, the precision was ≤ 3% (C = 10 μg L− 1, n = 15), limits of detection and quantification ranged from 0.1 to 0.3 μg L− 1 and 0.3–0.9 μg L− 1, respectively, and the maximum preconcentration factor was 30. The HF-SPME method was applied for the determination of trace metals in real gasoline and diesel samples.