Paraquat In Samples Research Articles

A rapid and reliable immunochromatographic strip for detecting paraquat poinsoning in domestic water and real human samples

Paraquat (PQ) is one of the most commonly used herbicides, but it has polluted the environment and threatened human health through extensive and improper usage. Here, a new naked-eye PQ immunochromatographic strip was developed to recognize PQ in domestic water and real human samples within 10 min based on a novel custom-designed anti-PQ antibody. The PQ test strip could recognize PQ at a concentration as low as 10 ng/ml, reaching the high-efficiency time-of-flight mass spectrometry detection level and identifying trace amounts of PQ in samples treated with a diquat (DQ) and PQ mixture. Notably, both the performance evaluation and clinical trial of the proposed PQ strips were validated in multiple hospitals and public health agencies. Taken together, our study firstly provide the clinical PQ-targeted colloidal gold immunochromatographic test strip designed both for environment water and human sample detection with multiple advantages, which are ready for environmental monitoring and clinical practice.

Determination of paraquat residue in plant-derived foodstuffs by high performance liquid chromatography-tandem mass spectrometry

A sensitive and selective method is presented for the determination of paraquat residue in fruits, vegetables, beans and grain by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Paraquat in samples was extracted with water and cleaned-up with a weak cation exchange (WCX) column to obtain an extract suitable for analysis using HPLC-MS/MS. The paraquat was separated by a CAPCELL PAK ST column (150 mm x 2.0 mm) and with acetonitrile-10 mmol/L ammonium acetate solution (adjusted to pH 4.0 by formic acid) as the mobile phase, and multiple reaction monitoring (MRM) was used with electrospray ionization in the positive ion mode. The calibration curve was linear between the peak area and the mass concentration of paraquat from 0.01 to 0.1 mg/L with the correlation coefficient of 0.993. Recoveries of paraquat spiked in samples at three levels ranged from 84.0% to 106.0% with the relative standard deviations of 7.8% - 18.8%. The limits of detection (LODs) of paraquat were 0.01 mg/kg in fruits and vegetables and 0.05 mg/kg in beans and grain. The LODs can meet the requirements of international maximum residue limit.

Application of internal quality control to the analysis of quaternary ammonium compounds in surface and groundwater from Andalusia (Spain) by liquid chromatography with mass spectrometry

A method has been developed for the simultaneous determination of paraquat (PQ), deiquat (DQ), chlormequat (CQ) and mepiquat (MQ) in water samples by liquid chromatography (LC) coupled with electrospray ionization mass spectrometry (MS). The LC separations of the target compounds, as well as their MS parameters, were optimized in order to improve selectivity and sensitivity. Separation was carried out in a Xterra C 8 column, using as mobile phase methanol–heptafluorobutyric acid (HFBA) in isocratic mode. The molecular ion was selected for the quantitation in selected ion monitoring (SIM) mode. Off-line solid-phase extraction (SPE) was applied with silica cartridges in order to preconcentrate the compounds from waters. Detection limits were in the range 0.02–0.40 μg l −1. Recovery range varied between 89 and 99.5% with precision values lower than 6%. The method has been applied successfully to the analysis of both surface and groundwater samples from agricultural areas of Andalusia (Spain), using well defined internal quality control (IQC) criteria. The results revealed the presence of deiquat and paraquat in some samples.