Parathion In Water Research Articles

Recombinant Organophosphorus acid anhydrolase (OPAA) enzyme-carbon quantum dot (CQDs)-immobilized thin film biosensors for the specific detection of Ethyl Paraoxon and Methyl Parathion in water resources

Organophosphates pesticide (OP) toxicity through water resources is a large concern globally among all the emerging pollutants. Detection of OPs is a challenge which needs to be addressed considering the hazardous effects on the health of human beings. In the current research thin film biosensors of recombinant, Organophosphorus acid anhydrolase (OPAA) enzyme along with carbon quantum dots (CQDs) immobilized in thin films were developed. OPAA-CQDs thin film biosensors were used for the specific detection of two OPs Ethyl Paraoxon (EP) and Methyl Parathion (MP) in river water and household water supply. Recombinant OPAA enzyme was expressed in E. Coli, purified and immobilized on the CQD containing chitosan thin films. The CQDs used for this purpose were developed by a one-pot hydrothermal method from phthalic acid and Tri ethylene diamine. The properties of CQDs, OPAA and thin films were characterized using techniques like XPS, TEM, XRD, enzyme activity and CLSM measurements. Biosensing studies of EP and MP were performed by taking fluorescence measurements using a fiber optic spectrometer. The analytical parameters of biosensing were compared against an estimation carried out using the HPLC method. The biosensing performance indicates that the OPAA-CQDs thin film-based biosensors were able to detect both EP and MP in a range of 0–100 μM having a detection limit of 0.18 ppm/0.69 ppm for EP/MP, respectively with a response time of 5 min. The accuracy of estimation of EP/MP when spiked in water resources lie in the range of ∼100–102% which clearly indicates the OPAA-CQD based thin film biosensors can function as a point-of-use method for the detection of OP pesticides in complex water resources.

Rapid determination of methyl parathion and fenthion residues based on surface-enhanced Raman spectroscopy

Methyl parathion (MP) and fenthion are both organophosphorus pesticides that have been widely used in agriculture. However, they significantly pollute the environment. A silver nanorod array chip prepared under low temperature conditions was designed to detect the residues of fenthion on the surface of fruit peel and methyl parathion in water. The results show that the characteristic peaks of MP were at 811, 855, 1158, 1236, and 1324 cm − 1 and the characteristic peaks of fenthion were at 853, 1156, 1224, and 1590 cm − 1. The vibrational modes of each peak were calculated using the density function theory. This method can detect MP in different water samples and fenthion on apple peel within 3 min without any complicated pretreatment. The results suggest that the method for rapid determination of organophosphorus pesticides based on surface-enhanced Raman spectroscopy was sensitive and reliable. It is expected that this method has great application potential in environmental pollution monitoring.

Fe2O3/Mn2O3 nanoparticles: Preparations and applications in the photocatalytic degradation of phenol and parathion in water

AbstractIn this study, nanoparticles of Fe2O3/Mn2O3 mixture were obtained using the sol–gel method. The synthesis uses the combination of polyvinyl alcohol (PVA) and tartaric acid (TA). Synthesized catalysts prove superior compared to those afforded from previous reports. To be specific, desired catalysts can be received at lower calcination temperature. Furthermore, their structures display higher uniformity in term of particle sizes. Finally, they show better performance for the photocatalytic degradation of model‐persistent organic compounds.

Colorimetric bio-barcode immunoassay for parathion based on amplification by using platinum nanoparticles acting as a nanozyme.

A competitive bio-barcode immunoassay is described for the trace detection of parathion in water, pear, cabbage, and rice samples. It is based on amplification by platinum nanoparticle acting as a nanozyme. Gold nanoparticles (AuNPs) were modified with (a) monoclonal antibodies (mAbs) against parathion, and (b) thiolated single-stranded DNA (ssDNA) oligonucleotides. Magnetic nanoparticles (MNPs) were functionalized with ovalbumin coupled with parathion hapten. Parathion and its hapten compete with mAbs on the surface of the AuNPs. Subsequently, the platinum nanoparticles (PtNPs) probe, which was functionalized with the complementary thiolated ssDNA (C-ssDNA), was added to the reaction mixture for the detection of parathion. The signal was catalytically amplified by coupling with platinum nanozyme using teramethylbenzidine and H2O2 as the chromogenic system. The immunoassay has a linear range that extends from 0.01-50μg·L-1, and the limit of detection is 2.0 × 10-3μg·L-1. The recoveries and relative standard deviations (RSDs) ranged from 91.1-114.4% and 3.6-15.8%, respectively. The method correlates well with data obtained by gas chromatography-tandem mass spectrometry (GC-MS/MS). Graphical abstract The parathion and the magnetic nanoparticles (MNPs) labelled with hapten-OVA competitively reacted to AuNPs modified with mAbs and thiolated DNA for thedetection of parathion. The signal was catalyzed by platinum nanozyme. The limit of detection for parathion is 2.0 ng·L-1.

Acetylcholinesterase Biosensor Based on Gold Nanoparticles/Nitrogen−Doped Vertically Oriented Reduced Graphene Oxide Prepared by Single−Step Electrodeposition

A novel acetylcholinesterase (AChE) biosensor based on gold nanoparticles/nitrogen−doped vertically oriented reduced graphene oxide (AuNPs/NVRGO) film was developed for the detection of organophosphorus pesticides (OPs). The AuNPs/NVRGO film was prepared by single−step electrodeposition of nitrogen−doped reduced graphene oxide (NRGO) in the presence of HAuCl4. This film resulted in excellent electrochemical response and electron−transfer efficiency because of the synergistic effect of AuNPs with NVRGO. In addition, the AChE biosensor exhibited a strong linear relationship for OPs concentrations ranging from 3.0 × 10−9 to 3.0 × 10−15 mol L−1 for malathion and 3.8 × 10−9 to 3.8 × 10−15 mol L−1 for methyl parathion. Under optimum conditions, the results displayed high sensitivity of the derived biosensor for monitoring malathion and methyl parathion in water down to detection limits of 3.0 × 10−16 mol L−1 and 2.3 × 10−14 mol L−1, respectively. The biosensor also revealed operational stability, satisfactory reproducibility, and good recovery. The proposed approach provides an effective and sensitive means of OPs detection because of its several advantages such as simplicity, low cost, and high accuracy.

Fabrication of AChE/SnO2-cMWCNTs/Cu Nanocomposite-Based Sensor Electrode for Detection of Methyl Parathion in Water

The work highlights inhibition-based Acetylcholinesterase (AChE) fabrication using composite nanomaterial comprising tin oxide nanoparticles (SnO2) and carboxylated multiwalled carbon nanotubes (cMWCNTs) for detection of pesticide methyl parathion (MP) in water samples. Working electrode AChE/SnO2-cMWCNTs/Cu exhibited high sensitivity with a linearity range of 1.0 μM to 160 μM and a minimum detection limit of 0.1 μM for MP in water. The fabricated electrode was found biocompatible and nontoxic which can be used to detect low concentrations of pesticide in water samples. The synergistic and facilitated electron transferring properties of SnO2-cMWCNTs/Cu made it an excellent support for immobilization of enzyme in sensing technology. The enzyme AChE was covalently immobilized with cMWCNTs using glutaraldehyde as crosslinking agent which has enhanced the storage stability and reusability of the method. The reusability attained was 30 times for 40 days when AChE/SnO2-cMWCNTs/Cu was stored at low temperature of 4°C. Developed sensor showed excellent analytical recovery of pesticide in water sample with negligible effect of interfering species. Also, AChE/SnO2-cMWCNTs/Cu was easily reactivated simply by varying pH of phosphate buffer. This method is fast, reliable, and accurate showing successful development of amperometric biosensor for detection of MP in water sample.

Non-enzymatic electrochemical platform for parathion pesticide sensing based on nanometer-sized nickel oxide modified screen-printed electrodes

Nanozyme-based electrochemical sensors have attracted much attention because of their low cost, sensitivity and remarkable stability under extensive environmental and industrial conditions. Interestingly, the physical characteristics of the nanomaterials in terms of size, shape, composition, surface area and porosity dominate the electrochemical processes at electrode surfaces. Herein, we explore nickel oxide nanoplatelets (NPs) modified screen-printed electrode-based nanozyme sensors that displays high electrochemical activity including stability, sensitivity, selectivity and applicability for organophosphate pesticide (Parathion) determination. Differential pulse voltammogram of NiO-SPE in presence of parathion showed a characteristic peak current at −1.0 V (vs. Ag/AgCl). The NiO-SPE platform allows determination of parathion over the concentration range of 0.1–30 µM with a limit of detection (LOD) of 0.024 µM. The sensing platform is found to detect parathion of interferences without compromising the sensitivity of the sensor. Such interesting features offer a sensitive determination of parathion in water, urine and vegetable samples.

Trichloroacetic acid assisted synthesis of gold nanoparticles and its application in detection and estimation of pesticide

Abstract Background Many analytical methods are available for detection of methyl parathion in water but they are not handy for on-site analysis. An attempt has been made to utilize stable GNP for methyl parathion detection by sensing the peak at 400 nm generated due to the interaction between methyl parathion and GNP. Methods GNP was produced by reduction of chloroauric acid solution by trichloroacetic acid in alkaline medium in presence of CTAB. Sensor properties of GNP were studied by varying the concentration of methyl parathion in gold sol from 0 to 500 ppm. Results and discussion GNP stabilized by CTAB showed only one peak at 532 nm and one broad peak near 300 nm was observed for pure methyl parathion. But as soon as methyl parathion was added in the GNP solution, one new peak at 400 nm developed in addition to the other two peaks. More interestingly, a quantitative decrease of the absorbance at 532 nm of GNP and increase of the absorbance at 400 nm, the new peak, were observed when methyl parathion concentration increased from 10 to 500 ppm. Conclusions The UV-VIS measurement and TEM images confirmed that the surfactant capped GNP can act as a colorimetric sensor for detection and estimation of methyl parathion pesticide present in water in ppm level.

A novel protocol for ultra-trace detection of pesticides: Combined electrochemical reduction of Ellman's reagent with acetylcholinesterase inhibition

This paper proposed a novel method for ultra-trace detection of pesticides combining electrochemical reduction of Ellman's reagent with acetylcholinesterase (AChE) inhibition. The amperometric biosensor, fabricated by immobilizing AChE on multi-walled carbon nanotubes-chitosan (MWCNTs-Chi) nanocomposites modified glassy carbon electrode, enjoyed high sensitivity owing to the excellent conductivity and favourable biocompatibility of MWCNTs-Chi nanocomposites. Meanwhile, the sensitivity of the biosensor was further enhanced using the electrochemical reduction signal of DTNB for determination. Under optimum conditions, methyl parathion was detected based on its inhibition effect on AChE activity and the subsequent change in electrochemical reduction response of DTNB. Good relationship was obtained between the reduction current and pesticide concentration in the ranges of 5.0×10−7 to 1.0×10−12M with a detection limit of 7.5×10−13M (S/N=3). Moreover, the proposed protocol was successfully employed for the determination of methyl parathion in water and soil samples.

Kinetic-spectrophotometric determination of methyl parathion in water and vegetable samples

A new selective and sensitive kinetic method has been developed for spectrophotometric determination of methyl parathion based on its inhibitory effect on the redox reaction between bromate and hydrochloric acid. The decolorization of neutral red by the reaction product was used to monitor the reaction spectrophotometrically at 530nm by measuring the change in absorbance at the fixed time of 5min after the initiation of the reaction. The variables affecting the rate of the reaction were investigated. Under the selected experimental conditions methyl parathion was determined in the range of 0.025–0.3μgmL−1. Sandell’s sensitivity and molar absorptivity for the system were found to be 0.0004μgcm−2 and 6.5×105Lmol−1cm−1 respectively. The proposed method was applied for the determination of methyl parathion in different vegetable and water samples with satisfactory results. The results were compared with those obtained by GC–MS, very similar values were found by the two methods.

Genetic surface-display of methyl parathion hydrolase on Yarrowia lipolytica for removal of methyl parathion in water

In this study, the mph gene encoding methyl parathion hydrolase from Pseudomonas sp. WBC-3 was expressed in Yarrowia lipolytica and the expressed methyl parathion hydrolase was displayed on cell surface of Y. lipolytica. The activity of methyl parathion hydrolase displayed on the yeast cells of the transformant Z51 was 59.5 U mg⁻¹ of cell dry cells (450.6 U per mL of the culture) in the presence of 5.0 mM of Co²⁺. The displayed methyl parathion hydrolase had the optimal pH of 9.5 and the optimal temperature of 40 °C, respectively and was stable in the pH range of 4.5-11 and up to 40 °C. The displayed methyl parathion hydrolase was also stimulated by Co²⁺, Cu²⁺, Ni²⁺ and Mn²⁺, and was not affected by Fe²⁺, Fe³⁺, Na⁺, K⁺, Ca²⁺ and Zn²⁺, but was inhibited by other cations tested. Under the optimal conditions (OD(600 nm) = 2.6, the substrate concentration = 100 mg L⁻¹ and 40 °C), 90.8 % of methyl parathion was hydrolyzed within 30 min. Under the similar conditions, 98.7, 97.0, 96.5 and 94.4 % of methyl parathion in tap water (pH 9.5), tap water (pH 6.8), seawater (pH 9.5) and natural seawater (pH 8.2) were hydrolyzed, respectively, suggesting that the methyl parathion hydrolase displayed on the yeast cells can effectively remove methyl parathion in water.

Determination of Methyl Parathion in Water and Its Removal on Zirconia Using Optical Enzyme Assay

A simple, miniaturized microplate chemiluminescence assay for determination of methyl parathion (MP) was developed in 384-microwell plates. Zirconia (ZrO(2)) was added in microwell for adsorption of acetylcholinesterase (AChE). The developed assay is based on inhibition of AChE by MP. A good dynamic range 0.008-1,000ng/mL was obtained for MP with limit of detection 0.008ng/mL. Intrabatch and interbatch reproducibility for miniaturized assay was obtained with % RSD up to 3.07 and 5.66, respectively. In 384 well plate formats, 70 samples were simultaneously analyzed within 20min with assay volume of 41.5μL. The application of developed assay was extended for MP remediation. Column containing ZrO(2) was utilized for remediation where MP was selectively adsorbed. Under optimized condition, adsorption of MP on ZrO(2) was found to be 98-99% with 2-h contact time in real water samples. Adsorption of MP on ZrO(2) column followed by quantification using developed bioassay provides a novel approach to monitor remediation. The applicability of assay was successfully extended for determination of MP in water samples after removal through ZrO(2).

Development of a competitive format sorbent assay for the determination of parathion in water using molecular imprinted polymer as specific sorbent carrier

A rapid, simple, and reliable competitive molecular imprinted polymer sorbent assay (MIPSA) was developed and validated for measurement of parathion in water samples. This assay employed a molecular imprinted polymer (MIP) that was synthesized with non-covalent imprinting method as capture reagent and p-aminoparathion conjugate of horseradish peroxidase ( para-HRP) as an enzyme label. The assay depended on a competitive binding reaction between the enzyme conjugate and analyte for the binding sites of the MIP. The optimized analysis conditions of 10 ng mL −1 para-HRP and 10 mg mL −1 polymer were found. The assay was acceptable to detect parathion in water samples under the optimized conditions, with a limit of detection of 50 ng mL −1. Mean analytical recoveries of added parathion in water samples ranged from 101.2% to 105%. The precision of the assay was satisfactory; relative standard deviation ranged from 4.3% to 6%.

Electrically assisted solid-phase microextraction combined with liquid chromatography–mass spectrometry for determination of parathion in water

A novel method for electrically assisted microextraction coupled to liquid chromatography–mass spectrometry was evaluated for determination of trace levels of parathion in water. A pencil lead electrode was used in a di-electrode system to extract parathion onto the electrode surface with a reductive potential applied. The optimum extraction conditions were found to be a potential of −600 mV for 60 s in pH 2 phosphate buffer solution. The parathion was desorbed statically for 1 min and dynamically for 3 min in the commercial SPME–HPLC desorption chamber, then analyzed with LC–APCI–MS/MS. The detection limit (LOD) for parathion in water was found to be 0.3 ng/mL. The proposed technique was demonstrated to be fast, sensitive and not require a solvent sample pretreatment.

Chemiluminescence based technique for the detection of methyl parathion in water and fruit beverages

Organophosphorus (OP) pesticides, being used extensively in agricultural practices, are highly toxic even at trace levels and their detection with high sensitivity is a challenging task. The present study addresses the development of a chemiluminescence (CL) based flow injection technique for the sensitive detection of methyl parathion (MP). Different fruit samples were spiked with MP and extracted according to the AOAC method. A mean recovery of 84.3%–103.1% was obtained for MP spiked fruit juice samples with 0.18%–9.29% reproducibility (RSD). The assay specificity was attributed to the use of highly specific immunological reactions. Competitive binding was monitored between free MP and MP-Horseradish Peroxidase (MP-HRP) with immobilized anti-MP IgY antibodies in an immunoreactor column. The unbound MP-HRP conjugate eluted out of the column as a non retained component and was reacted with urea-H2O2 (U–H2O2) and luminol. The photons generated during the biochemical interaction were determined by a photomultiplier tube (PMT) based detector, and were found to be directly proportional to the MP concentration. In the present investigation, IgY has proved advantageous over the IgG class of immunoglobulins in terms of yield, stability, cost effectiveness and enhancement of assay sensitivity. Using the proposed CL method, MP was detected in samples and showed linearity in the range of 0.001–500 ng mL−1 with a limit of quantification (LOQ) of 0.005 ng mL−1 and with a limit of detection (LOD) of 0.001 ng mL−1. The current findings show that this method can provide valuable information for the estimation of the pesticide traces in water and fruit beverages.

Removal of Methyl Parathion in Water, by Dugesia dorotocephala

The aim of this study was to determine the efficiency of Dugesia dorotocephala on Methyl parathion removal. An initial concentration of 1.25 microg mL(-1) of MeP was used to evaluate the removal capacity of planarian. A first-order removal kinetics was obtained with a disappearance rate constant (k(r)) of 0.49 days(-1) and 69% efficiency on contaminant removal. This is significantly different (p < 0.5) from the degradation occurring in control systems, leading us to conclude that D. dorotocephala effectively removes MeP from contaminated water.

Identification of Metabolites of Methylparathion in Plant, Water and Soil

ABSTRACT A GC-MS study was carried out to identify the decay products of methyl parathion in water, soil and rooted vegetable (radish) at different time intervals. The water (pH 5.5 and 8.0), soil (pH 7.5) and radish samples collected after the first half life shows the presence of O,O dimethyl O-p-nitro-2 or 3-hydroxyphenyl phosphoorothioate which persists upto the 30th day in the alkaline water and soil samples. However, in acidic water methyl parathion is oxidized to give methylparaoxon. Radish samples show the presence of two other products. These are identified as O,O-dimethyl o-p-aminophenyl -phosphoorothioate and O,O-dimethylo-p-hydroxyphenyl phosphoorothioate. The study indicates that the half life of methyl parathion in different media is nearly the same but its metabolites are not identical.

Complete oxidation of metolachlor and methyl parathion in water by the photoassisted Fenton reaction

Metolachlor [2-chloro- N-(2-methyl-6-ethylphenyl)- N-(2-methoxy-1-methylethyl)acetamide] or methyl parathion [ O,O-dimethyl-4-nitrophenyl phosphorothioate] at (1–2) × 10 −4 M was rapidly decomposed using a photoassisted Fenton reaction (Fe 3+/H 2O 2/u.v.). At 10 −2 M H 2O 2 and blacklight u.v. (300–400 nm) comparable in intensity to midday summer sunlight, metolachlor reacted in 8 min and was completely mineralized to HCl (40 min), inorganic N (7:1 ratio of NH 3 and HNO 3, > 2 h), and CO 2 (6 h). The aromatic ring was mineralized in 2.5 h. The transient organic intermediates identified—chloroacetate, oxalate, formate, serine, and several derivatives with the aromatic ring intact—indicate non-selective attack on the molecule. Under the same conditions, methyl parathion reacted in 5 min giving quantitative yields of HNO 3 and H 2SO 4 (5 min) and H 3PO 4 (30 min). Oxalic acid, 4-nitrophenol, dimethyl phosphoric acid, and traces of O,O-dimethyl-4-nitrophenyl phosphoric acid were identified as intermediates and shown to be oxidized further. Solutions of 14C-4-nitrophenol evolved HNO 3 concomitant with disappearance of starting material, and evolved 14CO 2 within 45 min. Based on the intermediates and their yields the initial oxidant attack on methyl parathion appears to be on the PS group leading to elimination of 4-nitrophenol and dimethyl phosphate. The results suggest that photoassisted Fenton oxidation can be a mild and effective remedy for dilute pesticide wastes.

Monoclonal antibody‐based ELISA for the detection of ethyl parathion

An enzyme‐linked immunosorbent assay (ELISA) using a monoclonal antibody for the detection of ethyl parathion has been developed. The assay is capable of detecting ethyl parathion in water or milk in the range 0.001–40 μg ml‐1. The specificity of the technique was studied by inhibition assay. Cross‐reactivity with related compounds showed that the antibody reacted with ethyl parathion, methyl parathion and reduced parathion but did not react significantly with the structurally related compounds paraxon, p‐nitrophenol, malathion and dimethoate. Cross‐reactions at 40 μg gl‐1, the highest concentration assayed, produced inhibition by paraxon (40%), p‐nitrophenol (30%), malathion (15%) and dimethoate (0%).

Changes in the aqueous behavior of parathion under varying conditions of pH

Factors affecting the stability of parathion in the aquatic environment were studied, with emphasis on pH. In 24-hr toxicity tests, using the midgeChironomus riparius, parathion was significantly more toxic at pH 6 than at pHs 4 and 8. While the data from toxicity tests suggested that pH may be important in determining the environmental fate of parathion, pH was found to be insignificant in controlling levels of parathion in water and organisms of aquatic microcosms adjusted to pHs 4, 6, and 8. After 7 days, parathion accounted for 29.7, 28.7, and 36.6% of total radioactivity in the water of microcosms held at pHs 4, 6, and 8, respectively. In abiotic water, however, no parathion breakdown was observed in 40 days at any of the three pH levels. These data demonstrate the importance of biotic factors, particularly microorganisms, in degrading parathion. Microorganisms which metabolize parathion in the microcosms were not adversely affected by changes in pH.