Use of 1‐octyl‐3‐methylimidazole hexafluorophosphate modified magnetic hyperbranched polyamideamine as sorbent for the extraction of pyrethroid insecticides from tea infusion

Abstract

Magnetic hyperbranched polyamideamine was carboxylated using succinic anhydride and modified further with 1‐octyl‐3‐methylimidazole hexafluorophosphate successively. The morphology and chemical composition of the prepared material was characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett‐Teller measurement, X‐ray photoelectron spectroscopy, etc. 1‐Octyl‐3‐methylimidazole hexafluorophosphate modified magnetic hyperbranched polyamideamine was used as sorbent in the magnetic solid‐phase extraction for the separation and enrichment of five pyrethroid insecticides from tea infusion. The magnetic solid‐phase extraction method proposed in this article has low method detection limits (0.53–0.71 ng/mL), acceptable coefficient of determination (0.9992–0.9998), wide linear ranges (2.5–500.0 ng/mL), and good repeatability (intraday: 1.2–6.3%; interday: 1.6–5.4%). In the detection of five pyrethroid insecticides in tea infusion, relative recoveries were in the range from 87.7 to 114.7% with satisfactory relative standard deviations (0.2–7.4%). With the aid of quantum chemistry calculations, the interaction energy between the sorbent and five pyrethroid insecticides was calculated, which proved the necessity of the modification of 1‐octyl‐3‐methylimidazole hexafluorophosphate.

Alien species water hyacinth realizes waste into treasure: The preparation of biomass sorbent to determine benzoylurea insecticides in tea products

“…So, related tea products are gradually increasing and loved by young people. The cultivation of tea is inseparable from the use of pesticides, and benzoylurea insecticide (BUs) is one of the most widely used pesticides [2,3]. However, the extensive and irrational use of BUs may lead to their residue in tea and pose a threat to consumer health.…”