Trifluralin In Water Research Articles

Highly sensitive and recognizable detection for trifluralin with alkyl-decorated fluorescent porous polymers

The sensing materials and portable devices with high sensitivity and specific recognition are urgently demanded for monitoring the pesticide residue in soil, water and food. Herein, two fluorescent porous polymers with carbazole-based chromophores decorated by n-butyls are synthesized through A3 + B2 and A3 + B4 condensation polymerizations, respectively. The hierarchical pores ranging from ultramicropore to mesopore are adjustable by varying the crosslinking density in the networks. The fluorescent quenching coefficient and limit of detection for trifluralin exceptionally reach 4.57 × 105 M−1 and 6.0 ppb, and the polymers exhibit ultra-sensitive recognizable ability for trifluralin in water. The quenching efficiencies for trifluralin in water, aqueous solutions of various cations and anions, vegetable juice and soil filtrate remain nearly the same. In particular, the fabricated polymer plates are portable and show visual fluorescent quenching for trifluralin solution at an extremely low concentration, and the plates can be easily recovered and repeatedly used. The results revealed in this manuscript are helpful for deeply understanding the effects of porosity parameters and alkyl-decorated chromophore groups on the sensitive and recognizable sensing mechanism for trifluralin.

Electrochemical sensing of trifluralin in water by fluconazole-immobilized Fe3O4/SiO2 nanomagnetic core–shell linked to carbon nanotube modified glassy carbon electrode; an experimental and theoretical modeling

A novel and sensitive method has been described for voltammetric study and determination of trifluralin, commonly used herbicide, based on its electrochemical oxidation on modified glassy carbon electrode (GCE) with multi-walled carbon nanotubes (MWCNT) and nanomagnetic core–shell coated with fluconazole (Fe3O4/SiO2 ~ FLU). CV studies indicated that the amine group of trifluralin oxidation process has a quasi-reversible and adsorption-like behavior in a mechanism with equal number of electrons and protons. The proposed sensor was found to quantify trifluralin by SWV in the range of 1.0 × 10−9–2.0 × 10−7 mol L−1, R2 = 0.998, detection limit (1.0 × 10−9 mol L−1) and repeatability (RSD = 1.99%, n = 10, for 1.0 × 10−7 mol L−1 trifluralin). The interpretations of the theoretical calculations and experimental results have shown good adaptation to discuss the outer sphere electron transfer (ET) process on the fluconazole-immobilized Fe3O4/SiO2 core–shell linked to carbon nanotube modified glassy carbon electrode. To further validate its possible application, the method was used for the quantification of trifluralin in water samples.

Multiresidue determination of herbicides in environmental waters from Primavera do Leste Region (Middle West of Brazil) by SPE-GC-NPD

A study on the presence of herbicides, namely simazine, metribuzin, metolachlor, trifluralin, atrazine and two metabolites, deisopropylatrazine (DIA) and deethylatrazine (DEA), was performed in ground and surface waters from Primavera do Leste region, Mato Grosso state (Middle West of Brazil). The analytical procedure was based on solid-phase extraction (SPE) with Sep-Pak C18 disposable cartridges and ethyl acetate for elution solvent. Residue levels were determined by gas chromatography with nitrogen-phosphorus detection. For most of the pesticides average recoveries at different fortification levels were >70% with relative standard deviation <19%. The recoveries of DIA and trifluralin in water were 25% and 56%, respectively, which were attributed to the incomplete retention of DIA and strong retention on the sorbing material and high volatility of trifluralin. Detection limits ranged from 0.023 to 0.088 µg L-1. This method was applied for the analysis of 5 superficial water samples and 28 groundwater samples, in places used for human consumption without previous treatment, collected in Primavera do Leste, Mato Grosso, Brazil. Results indicated that the highest level of contamination in a water sample was 1.732 µg L-1 for metolachlor, while metribuzin was the most frequently detected herbicide with maximum concentration of 0.351 µg L-1.

The photodecomposition of trifluralin in water.

The photodecomposition of trifluralin in water.