Dispersive solid-phase extraction using microporous metal-organic framework UiO-66: improving the matrix compounds removal for assaying pesticide residues in organic and conventional vegetables

Abstract An efficient dispersive solid-phase extraction method was developed to trace pesticide residues in commonly consumed vegetables. In this method, UiO-66 with uniform micropores was used as sorbent, and gas chromatography-mass spectrometry was applied to detect the pesticides. Thanks to the size sieving action of uniform micropores, UiO-66 directly extracted the target pesticides from vegetable matrices and excluded the relatively large matrix compounds. This well eliminated the matrix effect. The important experimental conditions were evaluated by orthogonal array experimental design. In optimized conditions, good linearity good linearity (R2 ≥ 0.99), detection limits (0.4-2.0 ng/g), recoveries (60.9-117.5%) and precision (relative standard deviations