Organic solvent-free solid-phase extraction of acetamiprid in food samples using Strep-Tag system integrated apta-magnetic sorbents

Abstract

A novel magnetic sorbent, named ABA-(Strep-tag II)-STMB, was prepared by modifying the acetamiprid-binding aptamer (ABA) onto Strep-Tactin-coated magnetic beads (STMBs) via Strep-tag II. The integration of the Strep-tag system allows the elution of the target by the addition of D-biotin, which can compete with Strep-tag II for the Strep-Tactin sites on the magnetic beads, instead of organic solvents. The sorbent showed good selectivity and reusability, and the extraction efficiency could still reach 90.5 % after 8 reuses. Under the optimized conditions, the developed magnetic solid-phase extraction (MSPE) method exhibited good linearity in the range of 0.1–100 μM, with the limits of detection (LOD) of 0.017–0.019 μM, and the limits of quantification (LOQ) of 0.057–0.066 μM. The relative standard deviations (RSDs) were below 5.51 %. The spiked recoveries were 84.4 %–96.0 %. The analysis results were in good agreement with those of the QuEChERS method.