Diazinon In Water Samples Research Articles

Separation and quantification of diazinon in water samples using liquid-phase microextraction-based effervescent tablet-assisted switchable solvent method coupled to gas chromatography-flame ionization detection.

This study used a liquid-phase microextraction-based effervescent tablet-assisted switchable solvent method coupled to gas chromatography-flame ionization detection as an eco-efficient, convenient-to-use, cost-effective, sensitive, rapid, and efficient method for extracting, preconcentrating, and quantifying trace amounts of diazinon in river water samples. As a switchable solvent, triethylamine (TEA) was used. In situ generation of CO2 using effervescent tablet containing Na2 CO3 and citric acid changed the hydrophobic TEA to the hydrophilic protonated triethylamine carbonate (P-TEA-C). CO2 removal from the specimen solution using NaOH caused P-TEA-C to be converted into TEA and led to phase separation, during which diazinon was extracted into the TEA phase. The salting-out process was helpful in enhancing extraction efficiency. In addition, a number of significant parameters that affect extraction recovery were examined. Under optimum conditions, the limit of detection and limit of quantitation were 0.06 and 0.2ng/ml, respectively. The extraction recovery percentage and pre-concentration factor were obtained at 95 and 190%, respectively, and the precision (inter- and intra-day, relative standard deviation %, n= 5) was <5%.

A chemiluminescence biosensor based on the peroxidase-like property of molybdenum disulfide/zirconium metal-organic framework nanocomposite for diazinon monitoring

BackgroundOrganophosphorus pesticides are widely used in agriculture owing to their high effectiveness as insecticides. Among these, diazinon is a common environmental contaminant that acts as an acetylcholinesterase (AChE) enzyme inhibitor. As the current methods are too expensive and time-consuming for routine analysis of diazinon, its trace monitoring by rapid and sensitive methods is critical to protect the environment and human health. ResultsA biosensor was introduced for the indirect detection of diazinon using a molybdenum disulfide/zirconium metal-organic framework (MoS2@MIP-202(Zr)) nanocomposite. The probe is based on the peroxidase mimic of the prepared nanocomposite on NaHCO3–H2O2 chemiluminescence system as well as the inhibitory effect of diazinon on the enzymatic activity of AChE. The chemiluminescence signal is gradually decreased with an increase in diazinon concentration, and there is a linear relationship between the analytical signal and diazinon concentration. Under the optimum conditions, the calibration plot is linear in the concentration range of 0.5–300.0 nmol L−1. The limit of detection and quantification limit of the method are 0.12 and 0.40 nmol L−1, respectively. The inter-day and intra-day relative standard deviations (% RSD n = 5, diazinon concentration; 100 nmol L−1) are 3.66 and 1.35%, respectively. The method was used for diazinon detection in real water samples, and the high relative recovery values for the spiked samples along with satisfactory results of a certified reference material analysis confirmed that the method is accurate and free from the matrix effect. Significance and noveltyA nano-probe based on the peroxidase-like property of MoS2@MIP-202(Zr) nanocomposite was developed for the first time for indirect detection of residue levels of diazinon in water samples. The high stability of the nanocomposite makes it a good alternative for natural peroxidase enzymes such as horseradish peroxidase with low stability.

Design of fluorescent method for sensing toxic diazinon in water samples using PbS quantum dots-based gelatin

In this current article, a chemical sensor was synthesized PbS functionalized with gelatin quantum dots for toxic diazinon. The measure of toxic diazinon was performed using concentration 0.5 µM, PbS quantum dot-gelatin nanocomposites sensor, pH 6, and time 50 s, wavelength 300 nm, in phosphate buffer solution. Under the optimum conditions, the detection limit linear range was obtained (0.01–20.0 µg L−1). The standard deviation of less than (1.0%), and detection limits (3S/m) of the method (0.01 µg L−1) and quantification (LOQ) of (0.099 µg L−1), for determination of toxic diazinon, was obtained. The observed outcomes confirmed the suitability recovery and a very low detection limit for measuring the toxic diazinon. The Chemical PbS Quantum Dot–Gelatin nanocomposites sensor as excellent sensor was applied to measure and analyze residue toxic diazinon in water samples.

Application of ecofriendly magnetic nanocomposite synthesized from natural materials for separation and determination of diazinon pesticide in real water samples

ABSTRACT In this study, a cheap, novel, ecofriendly and effective nanosorbent was synthesised with natural materials such as sand beach and eggshell for diazinon determination in natural water. The synthesised nanosorbent was successfully characterised using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), field emission scanning- electron microscopy (SEM), vibrating sample magnetometer (VSM) and Brunauer–Emmett–Teller (BET) methods. Effective parameters were optimised for the extraction of diazinon and determination was done by UV-Vis spectroscopy at 248 nm. The method was linear in the range of 50–400 µg L−1 and the limit of detection was 6.9 µg L−1. Adsorption kinetic and isotherm studies were performed. Also, for measurement of diazinon in water samples of Gilan province, sampling was performed from important points such as river water, Anzali lagoon, well water, agricultural streams, and tap water. The results shows good spiked recovery (97.6–103.4%) in all samples. The accuracy of the method was also confirmed by the student’s t -test with HPLC analysis of real samples.

Sol-gel/nanoclay composite as a sorbent for microextraction in packed syringe combined with corona discharge ionization ion mobility spectrometry for the determination of diazinon in water samples.

In this work, the microextraction in packed syringe technique combined with corona discharge ion mobility spectrometry was used for determining diazinon in water samples. A new porous composite of nanoclay and polysiloxane was prepared using a sol-gel process. An amount of 2.0mg of the sorbent was packed in a 250 μL syringe and used for extraction. A volume of 2mL of the sample was passed through the sorbent bed, and the entrapped analyte was eluted by 25 μL of methanol. Important parameters influencing the extraction performance were investigated. Under optimum experimental conditions, the detection limit for diazinon was 0.07ng/mL. The intra- and inter-day relative standard deviations were 5.0 and 12.3%, respectively. The calibration curve was linear in the concentration range from 0.2 to 20.0ng/mL (r2 =0.999). The applicability of the method was demonstrated by analyzing spiked real water samples and the spiking recoveries were in the range of 95 to 106%.

Automated sample preparation with extraction columns followed by liquid chromatography-ionspray mass spectrometry interferences, determination and degradation of polar organophosphorus pesticides in water samples

The determination of polar and/or thermally labile organophosphorus pesticides trichlorfon, dichlorvos, dimethoate, oxydemeton-methyl, mevinphos ( cis and trans), demeton-S-methyl, fenamiphos, fenitrothion, fenthion and diazinon in water samples was investigated using solid-phase extraction followed by liquid chromatography-ionspray mass spectrometry (LC-ISP-MS). Pesticides were spiked at 0.2 μg/l in ground water samples and 200 ml were preconcentrated by using an ASPEC XL system. To improve the recovery of the most volatile pesticides such as dichlorvos, a further drying step with a Baker Spe 12 G apparatus with the vacuum set at 15 p.s.i. was included. A further evaporation step was applied with a gentle stream of nitrogen. A variety of materials (Amberchrom, LiChrolut EN, cyclohexyl, SDB, C 18 and Isolute ENV) were used for the isolation of the target pesticides. The elution step took place at 1 ml/min, with a 5-min contact time between the eluent and the sorbent. LC-ISP-MS permitted the identification of diethyl and di- n-butyl phthalates present as impurities in the cartridge materials. The presence of transformation products of the pesticides, e.g., fenthion sulfoxide, was also observed. The influence of pH and the water matrix (distilled and ground water) on the extraction efficiency was examined. The use of LC-ISP-MS permitted cis- and trans-mevinphos to be distinguished in the water sample owing to the presence of a specific ion at m z 99 . the limits of detection of the overall method were in the range 0.01–0.20 μg/1 using LC-ISP-MS with selected-ion monitoring.