Method For Determination Of Atrazine Research Articles

Ultrasound-assisted emulsification-microextraction coupled to ion mobility spectrometry for monitoring of atrazine and simazine in environmental water

Triazine herbicides and some of their transformation products are considered as one of the most important classes of chemical pollutants owing to their widespread use and toxicity. Triazines and their degradation products have caused concern because they are toxic and persistent in water, soil, and organisms. The present paper describes the validation of ultrasound-assisted emulsification-microextraction (USAEME) method for determination of atrazine and simazine using ion mobility spectrometry (IMS) in environmental water. The parameters influencing the extraction efficiency such as sonication time, extraction solvent, extraction volume and salt concentration were investigated. Under the optimum conditions, enrichment factors was 170 and 150 with corresponding LOD of 8 and 12 μg/L for atrazine and simazine respectively . Linearity with a coefficient of estimation (r2) were >0.99 in the concentration level range of 15–1500 μg/L and 20–1700 μg/L for extraction of atrazine and simazine in water samples. The proposed method successfully was applied to screen of atrazine and simazine in environmental water.

Otimization of extraction solid phase method for determination of atrazine by gas chromatography

Atrazine (2-chloro-4-ethylamino-6-isopropylamino-striazina), a herbicine from the family of s-triazine, widely used all over the world, has been detected in ground and surface waters in worrying levels of concentration. This compound has a low potential for bioaccumulation, moderate adsorption and mobility in soil. One way 1 Dra.; Fisica; Professora do Colegio Estadual do Parana; Endereco: Avenida Joao Gualberto, 250, Alto da Gloria, CEP: 80030-000, Curitiba, Parana, Brasil; E-mail: crisneiverth@yahoo.com.br Ambiencia Guarapuava (PR) v.11 n.2 p. 475 482 Jan./Abr. 2015 ISSN 1808 0251 Recebido para publicacao em 09/05/2012 e aceito em 16/10/2014 DOI:10.5935/ambiencia.2015.02.14nt Ambiencia Revista do Setor de Ciencias Agrarias e Ambientais V.11 N.2 Jan./Abr. 2015 476 is to determine atrazine is by Gas Chromatography coupled to Mass Spectrometry (CG-MS), using for the sample preparation the extraction in solid phase (SPE), which eliminates interferences and pre-concentrates the sample into a single step. This research aimed to develop a methodology for analysis of atrazine in water using Solid Phase Extraction in Gas Chromatography coupled with the Mass Spectrometry. The recovery was studied at two concentration levels (0.2 and 2.0 mg L-1), comparing the SIM and MS / MS. For quantification, the SIM method showed a better recovery (98% and 105%) and coefficient of variation (1.6%) at a concentration of 2.0 mg L-1. The detection limit of the SIM mode was 0.20 ng L-1 and the method was tested in surface water and leachate water of undisturbed soil columns of three headwaters. Only two samples of leachate water had concentrations of atrazine above those permitted by law (2.0 mg L-1).

Improvement of Spectrophotometric Method for the Determination of Atrazine in Contaminated Water by Inducing of Mannich Reaction

<p>The objective of this study is to develop a simple and economic spectrophotometric method for the quantitative determination of atrazine. This method is based on the complexation of atrazine derivatization (dechlorinated atrazine [DA]) with a mixture of formaldehyde and ketone compound, as described by Mannich reaction. The complex was determined by UV-Vis absorption measurement and the ketone compound used was the uranine due to its high coefficient absorption. The UV spectrum of the complex shows maxima of absorption at 207 nm and at 227 nm. An internal standard was used to quantify the atrazine. There is a good linearity between the absorbance and the concentration in the range of 0.1 - 10 ug.mL<sup>-1</sup> of atrazine. The recovery value was 97 % and the limit of detection was 0.01 ug.mL<sup>-1</sup>. Real samples collected from irrigation local area were analyzed using this method and the estimated concentration of atrazine found in the mentioned river is 0.29 ± 0.011 ug.mL<sup>-1</sup>.</p>

Fabrication of a Novel Atrazine Biosensor and Its Subpart-per-Trillion Levels Sensitive Performance

The present study describes an atrazine biosensor with the detection limit of 0.1 part-per-trillion (ppt). The atrazine biosensor is fabricated on tyrosinase-immobilized vertical growth TiO(2) nanotubes (Tyr/TiO(2)-NTs), based on the inhibition of tyrosinase by atrazine. The designed Tyr/TiO(2)-NTs present excellent applicability in atrazine determination, with high sensitivity and stability, and rapid response. The outstanding sensing characteristics for atrazine is attributed to the appropriate bioelectrochemical interface of Tyr/TiO(2)-NTs, resulting from the preponderant tubular structure, excellent biocompatibility, and hydrophilicity of TiO(2)-NTs. The atrazine biosensor possesses a wide detection range from 0.2 ppt to 2 part-per-billion (ppb). The practical application of the biosensor is realized for the determination of atrazine and the analysis of its transport in soil samples. A new method for determination of atrazine in soil samples is thus established, which greatly simplifies the preparation procedure of sample and is helpful to evaluate the pollution risk of atrazine to soil, groundwater, and surface water.

Spectrophotometric method for determination of atrazine and its application to commercial formulations and real samples

A simple sensitive spectrophotometric method has been developed for the determination of atrazine in herbicide formulations and real samples. The method was based on the reaction of atrazine with pyridine to form a quaternary halide which in the presence of alkali forms a carbinol base. The heterocyclic ring of the carbinol base breaks and forms the glutaconic dialdehyde. The glutaconic dialdehyde group was coupled with sulfanilic acid to form a yellow coloured product having λ max 450 nm or coupled with aniline to form a orange red coloured product having λ max 480 nm. The Beer's law was obeyed over the range from 0.1 to 25 µg mL−1 and molar absorptivity 1.5 × 104 L mol−1 cm−1 for sulfanilic acid, and from 0.08 to 12 µg mL−1 and molar absorptivity 1.3 × 104 L mol−1 cm−1 for aniline were observed. The reaction conditions and other analytical parameters were optimised. The proposed method has been successfully applied for the analysis of commercial formulations and real samples.

Improved GC‐MS/MS Method for Determination of Atrazine and Its Chlorinated Metabolites in Forage Plants—Laboratory and Field Experiments

Analytical procedures using gas chromatography–ion trap tandem mass spectrometry (GC‐MS/MS) were developed to analyze atrazine (ATR) and its dealkylated metabolites in four forage species (switchgrass, tall fescue, smooth bromegrass, and orchardgrass). Atrazine, deethylatrazine (DEA), and deisopropylatrazine (DIA) were extracted with methanol (CH3OH) followed by liquid–liquid extraction and partitioning into chloroform, with additional cleanup by C18 solid‐phase extraction (SPE). Through the optimization of ionization conditions and ion storage voltages, the background noise of product ion spectra (MS/MS) was reduced dramatically, providing sub‐µg/kg detection limits. Mean recoveries of ATR, DEA, and DIA were 94.3, 105.6, and 113.1%, respectively. The estimated limit of detection (LOD) was 0.6 µg/kg for ATR, 1.3 µg/kg for DEA, and 0.3 µg/kg for DIA. These LODs were one to two orders of magnitude lower than those reported for other GC‐MS, GC‐MS/MS, high pressure liquid chromatography (HPLC)‐UV, or HPLC‐MS/MS procedures designed for food‐safety monitoring purposes. To validate the developed method, a field experiment was carried out utilizing three replications of four forage treatments (orchardgrass, tall fescue, smooth bromegrass, and switchgrass). Forage plants were sampled for analyses 25 days after atrazine application. DEA concentrations in C3 grasses ranged from 47 to 96 µg/kg, about 10‐fold higher than in switchgrass, a C4 species. The ATR and DIA concentrations were similar, ranging from 1.5 to 13.2 µg/kg. The developed method provided sufficient sensitivity to determine the fate of ATR and its chlorinated metabolites via plant uptake from soil or dealkylation within living forage grasses. It also represented significant improvements in sensitivity compared to previous GC methods.

Developing a continuous flow-square wave voltammetry method for determination of atrazine in soil solutions using the hanging mercury drop electrode

This work describes the development of a Continuous Flow-Square Wave Voltammetry method for determination of atrazine using the hanging mercury drop electrode. The best signal to noise ratio was obtained at the square wave frequency of 350 Hz and flow rate of 0.47 mL min-1. Under these conditions, the analytical curve obtained in 0.010 mol L-1 CaCl2 soil extracts in presence of 40 mmol L-1 BR buffer and 0.25 mol L-1 NaNO3 was linear for atrazine concentrations between 0.10 and 2.0 µg mL-1, with detection and quantification limits of 0.030 and 0.10 µg mL-1, respectively. The proposed method increased the analytical throughput in comparison with the batch methodology, allowing a sampling frequency of 72 h-1 to be accomplished. Besides, the sample consumption is significantly reduced, and only 341 µL are necessary for each analysis. The results obtained were similar to the ones obtained by HPLC, but the proposed method is faster and does not use organic solvents.

SIMULTANEOUS SPECTROPHOTOMETRIC DETERMINATION OF ATRAZINE AND DICAMBA IN WATER BY PARTIAL LEAST SQUARES REGRESSION

It is presented the development of a new and easy analytical method for the simultaneous determination of atrazine and dicamba in water. Under the experimental conditions proposed, atrazine showed a linear dynamic range of 0.3 to 4.9 µg mL-1, a limit of detection of 0.1 µg mL-1 and a limit of quantification of 0.3 µg mL-1; similarly, dicamba showed a linear dynamic range of 0.8 to 8.8 µg mL-1, a limit of detection of 0.2 µg mL-1 and a limit of quantification of 0.8 µ mL-1. Partial Least Squares Regression (Type 1) was applied for the resolution of spectral interferences between analytes, obtaining recovery percentages higher than 95 % for both compounds in synthetic mixtures. Finally, quantitative determination of both herbicides in tap, well and sea water samples, was carried out successfully by the proposed method, previous preconcentration of the analytes by solid phase extraction

Developing a sequential injection-square wave voltammetry (SI-SWV) method for determination of atrazine using a hanging mercury drop electrode

This paper describes the development of a sequential injection analysis method to automate the determination of atrazine by square wave voltammetry exploiting the concept of monosegmented flow analysis to perform in-line sample conditioning and standard addition. To perform these tasks, an 800 μL monosegment is formed, composed by 400 μL of sample and 400 μL of buffer/standard solution. To obtain an efficient homogenization, the sample solution is divided in five zones intercalated by four zones of the Britton–Robinson buffer (pH 2.0) in presence of appropriate concentration of NaNO 3 and varying atrazine standard concentrations. This mixture zone is isolated from the carrier solution by two 100 μL air bubbles. After homogenization in an auxiliary reaction coil the mixture zone is injected toward the flow cell, which is adapted to the capillary of a hanging drop mercury electrode, at a flow rate of 50 μL s −1. After a suitable delay time, the potential is scanned from −0.5 to −1.2 V versus Ag/AgCl using a frequency of 300 Hz and pulse height of 25 mV. The linear dynamic range is observed for atrazine concentrations between 1.16 × 10 −7 and 2.32 × 10 −6 mol L −1, obeying the linear equation i p = (−6.91 ± 0.07) × 10 8[atrazine] + (4 ± 8), with r 2 = 0.9996, for which the slope is given in nA L mol −1. The detection and quantification limits of the method are 2.1 × 10 −8 and 7.0 × 10 −8 mol L −1, respectively. The sampling frequency is 37 h −1, when the standard addition protocol is followed. This frequency can be increased to 42 h −1 if the protocol to obtain in-line calibration curve is used for quantification. The method was applied for determination of atrazine in spiked river water samples and its accuracy was evaluated by comparison with the batch standard addition approach, which revealed that there is no evidence of statistically significant differences between the two methods.