Detection Of Atrazine Research Articles

Highly sensitive atrazine fluorescence immunoassay by using magnetic separation and upconversion nanoparticles as labels.

A high-sensitivity fluorescence immunoassay for atrazine was established. It is making use of hydrophilic NaYF4:Yb/Er upconversion nanoparticles (UCNPs) conjugated to the anti-atrazine antibody as signal probe, and of polystyrene magnetic microspheres (PMMs) conjugated to the coating antigen as the capture probe. The coating antigen on the capture probe competes with atrazine for binding to the antibody on the signal probe to form the immuno complex. The complex is separated from the test system by magnetic action, and its green fluorescence is then measured at excitation/emission wavelengths of 980/552nm using a fluorescence spectrophotometer equipped with an external 980nm laser. The method was applied to the determination of atrazine in corn, rice, sugar cane juice, and river water. The immunoassay has a linear range that extends from 0.005 to 10μg·L-1. The assay also recognizes propazine and prometryn, and it therefore can be applied to detect these three herbicides simultaneously. Sugar cane juice and river water samples can be analyzed directly without any pretreatment. The detection limits for atrazine are 2ng·L-1 in sugar cane juice and river water samples, and 20ng·kg-1 in corn and rice samples. The recoveries of spiked samples range from 84.7 to 113.6%. Graphical abstract A sensitive fluorescence immunoassay combining magnetic separation for the detection of atrazine in cereal, juice, and water samples using NaYF4:Yb/Er upconversion nanoparticles as labels.

Fluorometric atrazine assay based on the use of nitrogen-doped graphene quantum dots and on inhibition of the activity of tyrosinase

A fluorometric assay is described for the determination of theherbicide atrazine. The assay is based on the use of tyrosinase and fluorescent nitrogen-doped graphene quantum dots (N-GQDs). The N-GQDs were synthesized via one-pot hydrothermal reaction starting from citric acid and ammonia. Their fluorescence excitation and emission maxima are at 355 and 435nm, and the quantum yield is 18%. Tyrosinase catalyzes the oxidation of dopamine to form dopaquinone which reduces the fluorescence of the N-GQDs through a dynamic quenching process. On addition of atrazine, the catalytic activity of tyrosinase is inhibited. This leads to less formation of dopaquinone and less reduction of fluorescence. The assay has a linear response in the 2.5-100ng·mL-1 atrazine concentration range, and the detection limit is 1.2ng·mL-1. The assay was applied to the determination of atrazine in spiked environmental water samples. Graphical abstract Schematic presentation of the fluorometric assay of atrazine detection based on tyrosinase-induced fluorescence (FL) quenching effect on the nitrogen-doped graphene quantum dots (N-GQDs) and inhibitory effect of atrazine on tyrosinase.

Electrospun tin (IV) oxide nanofiber based electrochemical sensor for ultra-sensitive and selective detection of atrazine in water at trace levels

Atrazine, a class 3a carcinogen, is a pesticide of chloro triazine family and is known to severely affect the human endocrine system upon consumption. The toxic effects of atrazine cause damage not only to the humans but also to animals and plants. In lieu of the detrimental effects of atrazine on environment, it is essential to develop a sensor platform capable of its detection in water. Here, we propose ultrasensitive electrochemical detection of atrazine using electrospun SnO2 nanofibers. In this study, the nanofibers have been characterized using Field Emission Spectroscopy, X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis-NIR spectroscopy and Fourier transform infrared spectroscopy (FTIR). Using a label-free transduction, we have detected atrazine in fairly low concentrations, with the limit of detection being 0.9 zM and the sensitivity being 4.11 (μA/μM)/cm2, in a wide dynamic detection range varying from 1 zM to 1 μM. Furthermore, we have reported atrazine detection in trace levels in spiked real time water samples, which is an essential step in ensuring that the sensing platform can be deployed for practical applications. In addition to this, the sensor exhibits excellent selectivity, reasonable stability (when stored at 4 °C), and good interference-resistance.

Bifunctional S, N-Codoped carbon dots-based novel electrochemiluminescent bioassay for ultrasensitive detection of atrazine using activated mesoporous biocarbon as enzyme nanocarriers

A novel and ultrasensitive electrochemiluminescent (ECL) bioassay has been developed for the detection of atrazine (ATZ), whereby bifunctional S, N-codoped carbon dots (S, N-CDs) and activated mesoporous bicarbons (BCs) have been innovatively integrated to synergistically amplify the ECL signal. When endogenous dissolved O2 is used as a coreactant, its sluggish reduction hinders the enhancement of ECL intensity of the luminophore, thus restricting its further application in bioanalysis. Here, bifunctional S, N-CDs severe as not only the ECL luminophore but the coreaction accelerator of dissolved O2 to generate more intermediates to boost the coreaction without using any other coreactant and coreaction accelerator. The as-formed nanoarchitectures of BCs possess enlarged surface area as the nanocarriers. They could provide adequate active sites for immobilization of tyrosinase (Tyr), which greatly prompts the ECL bioassay applications. Such a smart integration of bifunctional S, N-CDs, activated mesoporous BCs and the enzyme inhibition reaction achieves a unique and attractive high-performance signal-on ECL bioassay, realizing ultrasensitive detection of ATZ. Under the optimal condition, this bioassay exhibits two linear ranges, from 0.0001 to 0.01 μg L−1 and 0.01–20 μg L−1 with a detection limit of 0.08 ng L−1 at signal to noise ratio of 3. The as-fabricated assay is sensitive and economical, opening a new way for the enhancement of ECL signal output and a versatile strategy for ultrasensitive ECL bioanalysis.

Sensitive surface-enhanced Raman scattering detection of atrazine based on aggregation of silver nanoparticles modified carbon dots

The development of precise detection methods with simply operation for pesticides in various environmental samples is a particular challenge. Here a highly sensitive surface-enhanced Raman scattering (SERS) approach for the selective detection of trace atrazine was proposed with R6G as a Raman reporter, which was adsorbed on silver nanoparticles modified carbon dots. The latter were prepared by the reduction of Ag+ by carbon dots. In the presence of atrazine, the aggregation of the modified carbon dots due to the interaction between silver nanoparticles and atrazine led to great enhancement of the SERS signal of R6G. Under optimal assay conditions, the limit of quantification was estimated to be 10 nM, which matched with the standard for drinking water quality of China and WHO defined limit. A good linear response to atrazine was found in the concentration range of 10–1000 nM with the relative standard deviations between 1.8% and 5.6%. The determination of atrazine in real water samples was also carried out to confirm the practicability of the proposed method, which showed the recoveries from 95% to 117.5%. The target induced aggregation for enhancing the signal offered great potential for sensitive on-site detection of atrazine in environments.

Design of a facile and label-free electrochemical aptasensor for detection of atrazine

A facile and label-free electrochemical aptasensor for detection of atrazine (ATZ) was designed based on nickel hexacyanoferrate nanoparticles (NiHCF NPs) and electrochemically reduced graphene oxide (ERGO). Because of ERGO perfect electrochemical conductivity and large surface area, it was first modified on glassy carbon electrode (GCE) surface by electrochemical reduction. NiHCF NPs were immobilized on ERGO/GCE as a signal probe with well-defined peaks and good stability. Subsequently, gold nanoparticles (Au NPs) were electrodeposited on NiHCF NPs/ERGO to anchored aptamer and increase the conductivity and stability of the electrode. When ATZ was added, ATZ-aptamer complexes generated with poor conductivity on the sensor surface increased the hindrance of electron transfer, leading to electrochemical signal decrease. The signal change was used to detect ATZ quantitatively. The designed aptasensor exhibited good analytical performance for determining ATZ. A linear curve was obtained in the range of 0.25–250 pM with a low detection limit of 0.1 pM, and it showed perfect selectivity for ATZ in the presence of diverse interferents. Meanwhile, the electrochemical aptasensor was employed to evaluate ATZ content in the samples.

Simultaneous Determination of Atrazine, Pendimethalin, and Trifluralin in Fish Samples by QuEChERS Extraction Coupled With Gas Chromatography-Electron Capture Detection

A rapid, simple, and dependable method was developed and validated for the simultaneous determination of atrazine, pendimethalin, and trifluralin in fish samples. Target analytes were extracted and purified by the modified QuEChERS method prior to analysis. Ultrasound-assisted extraction (10 min) was used to improve the extraction efficiency of classical acetonitrile extraction. The organic phase was then cleaned using dispersive solid-phase extraction with 150 mg primary secondary amine and 100 mg C18-bonded silica sorbents. GC with electron capture detection was used for determination. The method resulted in good linearity (R2 = 0.9973–0.9998) and low limits of detection and quantification (0.015–0.60 and 0.050–2.0 μg kg−1). Recoveries ranged from 76.8 to 94.6% with repeatability between 2.3 and 3.8% and reproducibility between 3.4 and 4.8%. The performance parameters demonstrated the method adequacy for the detection and quantification of atrazine, pendimethalin, and trifluralin residues in freshwater fish.

Label free, electrochemical detection of atrazine using electrospun Mn2O3 nanofibers: Towards ultrasensitive small molecule detection

Atrazine, a pesticide of chloro-triazine family and a class 3a carcinogen, is known to severely affect human endocrine system. In light of its detrimental environmental effects, ensuring its easy and ultrasensitive detection is highly essential. In this paper, we demonstrate facile and label free electrochemical detection of atrazine, using electrospun manganese oxide nanofibers (MNF). Here, we report an anti-atrazine-antibody based immunosensor, based on low bandgap Mn2O3 nanofibers, for ultrasensitive and highly selective detection of atrazine. The electrospun nanofibers used in this work were characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and UV–vis Spectroscopy. The proposed platform was able to detect atrazine in the concentration range of 10−21 g/mL, which in comparison to the previously reported atrazine sensors is a fairly superior performance. The observed lower limit of detection (LOD) was 0.22 × 10−21 g/mL, with a sensitivity of 52.54 (kΩ/μg mL−1)/cm2. We have also demonstrated atrazine detection in spiked water samples, so as to demonstrate that the proposed platform is suitable for real-time applications. Furthermore, the sensing platform is label free, comprising of a simple protocol and hence is facile in nature.

Quick and Easy Modification of Glassy Carbon Electrodes with Ionic Liquid and Tetraruthenated Porphyrins for the Electrochemical Determination of Atrazine in Water

AbstractAtrazine is a pesticide used to control broadleaf weeds, however its wide distribution and its high persistence in the soil and in surface waters has resulted in a public and environmental health problem. Present results shows the design, construction and characterization of glassy carbon electrodes modified with tetrarutenated metalloporphyrin (M=Ni (II) and Zn (II)) and 1‐butyl‐3‐methylimidazolium bis (trifluoromethylsulfonyl) imide, BMIMNTF2. The modification was reproducible and sensitive for the electrochemical detection of atrazine in neutral media. The detection limit was 230 nM when using GC/BMIMNTF2/ZnTRP and 540 nM with GC/BMIMNTF2/NiTRP, meaning that his methodology can be a feasible and inexpensive way to detect atrazine in trace levels.

Configuration of molecular imprinted polymer for electrochemical atrazine detection

This paper addresses the specific ability of molecular imprinted polymers (MIPs) to bind the template. MIPs for atrazine with various monomer:template and crosslinker:template ratios were prepared using bulk polymerization process. In order to obtain conditions closer to real wastewater test cases, the degree of the imprinting factor by the selection of solvent (methanol and water) was studied and compared. The polymer tested in methanol did not demonstrate good recognition of atrazine. In addition, the imprinting factors increased significantly when the imprinted polymers were tested in water solvent by 45%. Based on Scatchard analysis, the MIP was dependent upon low atrazine concentration (up to 40 mg/L) as the cavities formed in the MIP proved the cavities effects. An electrochemical analysis was done in order to prove that the method can be used as a quantitative analysis of atrazine concentration detection in water solution.

Origami multiple paper-based electrochemical biosensors for pesticide detection

Herein, we propose the first three-dimensional origami paper-based device for the detection of several classes of pesticides by combining different enzyme-inhibition biosensors. This device was developed by integrating two different office paper-based screen-printed electrodes and multiple filter paper-based pads to load enzymes and enzymatic substrates. The versatile analysis of different pesticides was carried by folding and unfolding the filter paper-based structure, without any addition of reagents and any sample treatment (i.e. dilution, filtration, pH adjustment). The paper-based platform was employed to detect paraoxon, 2,4-dichlorophenoxyacetic acid, and atrazine by exploiting the capability of these different types of pesticides (i.e. organophosphorus insecticides, phenoxy-acid herbicides, and triazine herbicide) to inhibit butyrylcholinesterase, alkaline phosphatase, and tyrosinase, respectively. The degree of inhibition correlating to the quantity of pesticides was evaluated by chronoamperometrically monitoring the enzymatic activity in the absence and in the presence of pesticides by using a portable potentiostat. To improve the sensitivity, the paper-based electrodes were modified with carbon black alone in the case of platforms for 2,4-dichlorophenoxyacetic acid and atrazine detection, or decorated with Prussian blue nanoparticles for the detection of paraoxon. The paper-based device was applied for the detection of paraoxon, 2,4-dichlorophenoxyacetic acid, and atrazine at ppb level in both standard solutions and river water sample. The accuracy of this origami multiple paper-based electrochemical biosensor was evaluated in river water by recovery studies, obtaining satisfactory values (e.g. for paraoxon 90 ± 1% and 88 ± 2%, for 10 and 20 ppb, respectively). The proposed three-dimensional origami paper device allows for rapid, cost-effective and accurate pesticide detection in surface water as a result of combining filter and office papers, screen-printing, wax-printing and nanomaterial technology.

Development of Ultra-sensitive Method for Determination of Trace Atrazine Herbicide in Environmental Water Using Magnetic Graphene Oxide-Based Solid-Phase Extraction Coupled with Dispersive Liquid-Liquid Microextraction Prior to Gas Chromatography-Mass Spectrometry

Atrazine is one of the most widely used herbicides and has caused much concern about its toxic effects on human and ecosystem. In the present work, a new and efficient method for ultra-trace determination of atrazine in water was developed, using magnetic graphene oxide-based solid-phase extraction combined with dispersive liquid-liquid microextraction, followed by gas chromatography-mass spectrometric determination. The effects of sample pH, contact time, type and volume of elution solvent and extraction solvent, desorption time, and salt addition on the extraction efficiency of atrazine were examined and optimized. Under the optimum conditions, an enrichment factor of 1033 and a detection limit of 0.6 ng L−1 for atrazine were achieved. The developed method was applied to the detection of atrazine in river water, lake water, pond water, and groundwater samples, with spiked recovery of 96–102% and RSD of 2.9–10.5%. Therefore, the proposed method allows proper monitoring of trace atrazine in various environmental waters.

Noncompetitive Homogeneous Detection of Small Molecules Using Synthetic Nanopeptamer-Based Luminescent Oxygen Channeling.

Our group has previously developed immunoassays for noncompetitive detection of small molecules based on the use of phage borne anti-immunocomplex peptides. Recently, we substituted the phage particles by biotinylated synthetic anti-immunocomplex peptides complexed with streptavidin and named these constructs nanopeptamers. In this work, we report the results of combining AlphaLisa, a commercial luminescent oxygen channeling bead system, with nanopeptamers for the development of a noncompetitive homogeneous assay for the detection of small molecules. The signal generation of AlphaLisa assays relies on acceptor-donor bead proximity induced by the presence of the analyte (a macromolecule) simultaneously bound by antibodies immobilized on the surface of these beads. In the developed assay, termed as nanoAlphaLisa, bead proximity is sustained by the presence of a small model molecule (atrazine, MW = 215) using an antiatrazine antibody captured on the acceptor bead and an atrazine nanopeptamer on the donor bead. Atrazine is one of the most used pesticides worldwide, and its monitoring in water has relevant human health implications. NanoAlphaLisa allowed the homogeneous detection of atrazine down to 0.3 ng/mL in undiluted water samples in 1 h, which is 10-fold below the accepted limit in drinking water. NanoAlphaLisa has the intrinsic advantages for automation and high-throughput, simple, and fast homogeneous detection of target analytes that AlphaLisa assay provides.

Rapid “turn-on” detection of atrazine using highly luminescent N-doped carbon quantum dot

Nitrogen doped carbon quantum dot based highly selective luminescent probe has been designed for the detection of herbicide atrazine. Nitrogen doped carbon quantum dot with PLQY 28% has been prepared from hydrothermal treatment of orthophenylene diamine. The turn-on fluorescence of the probe on addition of atrazine is attributed to aggregation induced fluorescence enhancement of amine functionalized carbon dot. The hydrogen bonding interaction of surface amine groups of carbon dot probe and atrazine makes the probe selective and ultrasensitive towards atrazine even in presence of other pesticides and metal ions. The limit of detection for atrazine sensing was found to be 3 pM, which is the lowest among all reported methods for the detection of atrazine. Due to low detection limit the utility of the developed sensor has also been explored in real agricultural samples. Owing to the excellent luminescence property and photostability this fluorescent probe can also be utilised to detect atrazine in bacterial cell by imaging.

High sensitive ELISA for detection of atrazion

To set up ELISA for detection of atrazine with high precision. The reaction condition of indirect-ELISA was optimized, including atrazine-ovalbumin(AT-OVA) concentration and primary antibody concentration, organic solvent, goat anti-rat immunoglobin G-horseradish peroxidase(IgG-HRP) concentration. The actual samples were detected by the ELISA method established in our laboratory. Then the ELISA method was compared with the HPLC. The specification curve of indirect-ELISA was set up after optimization. The relation coefficient R2=0.9958. The limit of detection (LOD) was 1.972 ng/ml. The percent recovery of the actual samples was in range of 80%~120%. The ELISA detection sensitivity was higher than the HPLC in the range of 0 ng/ml~6 ng/ml atrazine. The ELISA to detect atrazine has good specificity and high precision. And it can be applied in testing real atrazine samples replacing of the large-scale instrument.

TriPleX™ waveguide-based fluorescence biosensor for multichannel environmental contaminants detection

In order to realize the multi-analyte assays for environmental contaminants, an optical biosensor utilizing laser-induced fluorescence-based detection via the binding of biomolecules to the surface of an integrated TriPleX™ waveguide chip on a glass substrate (fused silica, FS) is described. As far as we know, this is the first demonstration of using the TriPleX™ technology to fabricate the waveguide chip on a FS substrate. The sensor consists of 32 individually addressable sensor patches, which were formed on the chip surface by exploiting 3 Y-junction splitters, creating four equal rows of eight evanescently excited windows in parallel. The basic low-loss SiO2/Si3N4 TriPleX™ waveguide configuration in combination with on-chip spotsize convertors allows for both high fiber-to-chip coupling efficiency and enables at the same time individually optimized high chip surface intensity and low patch-to-patch deviation. Moreover, the complementary metal-oxide-semiconductor compatible fabrication of waveguide chip allows for its mass production at low cost. By taking MC-LR, 2,4-D, atrazine and BPA as the model analytes, the as-proposed waveguide based biosensor was proven sensitive with the detection limits of 0.22 μg/L for MC-LR, 1.18 μg/L for 2, 4-D, 0.2 μg/L for atrazine and 0.06 μg/L for BPA. Recoveries of the biosensor towards simultaneous detection of MC-LR, 2, 4-D, atrazine and BPA in spiked real water samples varied from 84% to 120%, indicating the satisfactory accuracy of the established technology.

Multiplex highly sensitive immunochromatographic assay based on the use of nonprocessed antisera.

The format of an immunochromatographic multiassay is first proposed with native antisera and a universal conjugate of antispecies antibodies with gold nanoparticles. This format allows (1) the exclusion of purification and conjugation stages for specific antibodies and (2) significant reduction of the concentration of specific antibodies in the system. The independent use of specific antibodies and a conjugated marker provided a low detection limit and high signal intensity. The proposed format was implemented for the simultaneous detection of two herbicides. The instrumental limits for the detection of atrazine and chlorsulfuron were 0.1 and 0.7 ng/mL, respectively, and the analysis time was 20 min. The suitability of the test system for monitoring these herbicides in nontreated apple and blackcurrant juices is shown. The assay technique is simple, sensitive, and easily transferrable to any other antigen. Graphical abstract The proposed format of the immunochromatographic multiassay is based on the use of native antisera and a universal conjugate of antispecies antibodies with gold nanoparticles. In this way purification and conjugation stages for specific antibodies are excluded, and the concentrations of specific antibodies and the conjugated marker can be varied independently to obtain a low detection limit.

Cantilever nanobiosensor using tyrosinase to detect atrazine in liquid medium

ABSTRACTThe aim of this study was to develop a cantilever nanobiosensor for atrazine detection in liquid medium by immobilising the biological recognition element (tyrosinase vegetal extract) on its surface with self-assembled monolayers using gold, 16-mercaptohexadecanoic acid, 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride/n-hydroxysuccinimide. Cantilever nanobiosensors presented a surface compression tension increase when atrazine concentrations were increased, with a limit of detection and limit of quantification of 7.754 ppb (parts per billion) and 22.792 ppb, respectively. From the voltage results obtained, the evaluation of atrazine contamination in river and drinking water were very close to those of the reference sample and ultrapure water, demonstrating the ability of the cantilever nanobiosensor to distinguish different water samples and different concentrations of atrazine. Cantilever nanosensor surface functionalization was characterised by combining polarisation modulation infrared reflection-absorption spectroscopy and atomic force microscopy and indicating film thickness in nanometric scale (80.2 ± 0.4 nm). Thus, the cantilever nanobiosensor developed for this study using low cost tyrosinase vegetal extract was adequate for atrazine detection, a potential tool in the environmental field.

Atrazine residues in Irish potatoe (<em>Solanum tuberosum</em> L.) varieties from three selected areas in Plateau State, Nigeria

Atrazine is a pre-emergent herbicide used for the control of broad-leaf weeds that has residual activity in the environment. Extensive use of atrazine (strength of 800 g/kg Atrazine 50% WP) in Irish potato production in Plateau State, Nigeria has prompted this study to evaluate the atrazine residue levels in Irish potato varieties in three selected (Mangu, Jos South and Bokkos) areas of Plateau State. A questionnaire-based survey was conducted to determine the types and extent of herbicides used by farmers cultivating Irish potatoes. Samples of four Irish potato varieties: Diamant, Marabel, Christian Lady and Yellow and soils at 0-15cm depth were collected from each of the three Local Government Areas (LGAs). All the samples were subjected to chemical extractions using standard procedures and the extracts were analyzed for atrazine residues using spectrophotometer. Data were analysed using descriptive statistics and ANOVA at p=0.05. Results showed 63.6% of farmers using synthetic herbicides on their farms, while 76.27% used atrazine as their preferred herbicide over paraquat 23.73%. Soil samples from Mangu had significantly highest value of 9.98 mg/kg of atrazine residues and from the Diamant variety with no detection of atrazine in soil samples from other selected LGAs and their respective varieties. The Yellow variety from both Jos South and Bokkos had the highest values of 3.32 mg/kg and 3.13 mg/kg atrazine herbicide residues, while the least value of 1.51 mg/kg was from Diamant variety in Bokkos. However, trazine residue was not detected in Yellow, Marabel and Christian lady varieties from Mangu, Jos South and Bokkos, respectively. This study showed high atrazine residues with concentrations above 0.05 mg/kg and 0.1 mg/kg (US EPA acceptable maximum residue level) in the soil and Irish potato samples, respectively. This atrazine pesticide over time could lead to bioaccumulation in living organisms, food chain and ecosystem.

Ιmpedimetric nanoparticle aptasensor for selective and label free pesticide detection

An impedimetric label-free aptasensor for the simultaneous and highly selective detection of two pesticides is presented. The sensor is based on the combination of self-assembled platinum nanoparticle two-dimensional films (produced in room temperature via the magnetron sputtering technique) and target specific nucleic acids (a.k.a. aptamers). The platinum nanoparticle films have been deposited on top of SiO2 substrates previously patterned with interdigitated electrodes. The surface of the device has been chemically modified in order to enhance the subsequent aptamer deposition and immobilization. Two distinctive aptamer configurations have been employed in order to facilitate capturing and detection of two pesticides, namely acetamiprid and atrazine. Successful binding events between aptamer and target induce a shift in the impedance of the aptasensor which can be attributed in charge transport hindrance through the nanoparticle film. The incorporation of the nanoparticle film in the fabrication of the aptasensor significantly improves the performance of the device if compared to “naked” interdigitated based aptasensors, allowing the highly sensitive and selective detection of acetamiprid and atrazine down to 0.6×10−11M and 0.4×10−10M respectively.