3-Aminophenol-glyoxylic acid resin for the determination of triazine herbicides in tomatoes

A facile and efficient method for the determination of triazine herbicides in tomato samples was developed by employing 3-aminophenol-glyoxylic acid resin microspheres as a solid-phase extraction adsorbent followed by high performance liquid chromatography analysis. These resin microspheres were synthesized by a simple green precipitation polymerization method, and a range of functional groups (hydroxyl, amino, carboxylic group) were introduced through the 3-aminophenol and glyoxylic acid components. The as-prepared resin microspheres were characterized by scanning electron microscopy, Fourier transform infrared spectrometry, and thermal gravimetric analyzer. The resin microspheres exhibited a good adsorption rate, large adsorption amount, and short adsorption equilibrium time (almost in ∼5 min). Under the optimal extraction and determination conditions, a good linearity was obtained in the range of 0.025-7.5 μg g^-1 (r² ≥ 0.9997) for atraton, ametryn, and prometryn. The limits of detection of atraton, ametryn, and prometryn were 0.57, 0.75, and 1.06 μg kg^-1, respectively. The intra-day and inter-day precisions expressed as relative standard deviations were in the ranges of 1.8-3.2% and 1.7-4.1%, respectively. In addition, the recoveries at three spiked levels ranged from 85.1 to 97.7% with the relative standard deviation ≤ 5.4% (n = 3). This novel method is simple and accurate and has proved to be a reliable alternative method for the determination of triazine herbicides in tomato samples.