Determination Of Organophosphorus Pesticides Research Articles

A luminescent probe based on terbium-based metal-organic frameworks for organophosphorus pesticides detection.

Terbium-based metal-organic frameworks (Tb-MOF) prepared under mild conditions was utilized to construct a fluorescence probe for determination oforganophosphorus pesticides (OPs) coupled with acetylcholinesterase (AChE), acetylcholine chloride (Ach), and choline oxidase (CHO). Since OPs have obvious inhibition on the activity of AChE in the Tb-MOF/ACh/CHO/AChE system, the detection of OPs was accomplished by restoring the fluorescence of Tb-MOF resulting from reduced production of H2O2. By taking chlorpyrifos (CPF) as a pesticide model, the method exhibits high sensitivity in the linear range 0.1-4.0μg·L-1 with the limit of detection (LOD) of 0.04μg·L-1 under optimum conditions (λex = 280nm, λem = 544nm). The Tb-MOF/ACh/CHO/AChE fluorescence system has high selectivity for CPF. Themethod was successfully applied to the detection of CPF in tap water and strawberry samples (recovery of 87.36-115.60% for tap water and 95.04-103.20% for strawberry). Free from complicated fabrication operation, the Tb-MOF-based system is rapid, simple, and stable, which provides a reference and new way for the design of OPs fluorescent probes in the future.

Designing Hierarchically Porous Single Atoms of Fe-N5 Catalytic Sites with High Oxidase-like Activity for Sensitive Detection of Organophosphorus Pesticides.

Recently, single-atom catalysts (SACs) have been used to construct biosensors for the determination of organophosphorus pesticides (OPs). However, most nanozymes including SACs are peroxidase-like enzymes and require highly toxic and unstable hydrogen peroxide (H2O2) as a co-reactant to generate reactive oxygen species. Inspired by the heme site of cytochrome c oxidases (Ccos), the construction of Fe-N5-coordinated SACs by introducing axial N ligands is expected to bind O2 to generate active metal-oxygen intermediates. Herein, a SAC with an Fe-N5 active center confined by hierarchically porous carbon nanoframes (Fe SAs/N5-pC-4) was prepared by a polymerization-pyrolysis-evaporation-etching strategy, and its underlying enzyme-like mechanism was uncovered through experiments and density functional theory calculations. The 100% metal atom utilization, increased accessible active sites, accelerated mass transfer, excellent hydrophilicity, and an electron-driven mechanism of axial N endow the SAC with enhanced oxidase-like activity. Notably, its catalytic rate constant (0.398 s-1) is 569 times greater than that of the commercial Pt/C catalyst. Similar to the catalytic mechanism of Ccos, O2 can be converted into reactive oxygen species, avoiding the use of co-reactant H2O2 effectively. In addition, based on the inhibitory effect of thiols on the active site of Fe SAs/N5-pC-4, a biosensor was constructed and applied to the colorimetric analysis of OPs. This provides a facile, cost-effective method for efficient OP screening at sites to help control their contamination.

Microextraction of organophosphorus pesticides on a screw coated with PAN/calcined ZnMgAl-LDH electrospun nanofibers.

The present research is an attempt to expand the recently reported microextraction on screw method. For this purpose, polyacrylonitrile/calcined ZnMgAl-LDH nanofiber was fabricated by the electrospinning technique on the surface of a screw. It was applied tothe extraction of organophosphorus pesticides (OPP)from agricultural samples. The separation and determination of OPPs were carried out by gas chromatography-mass spectrometry. The characterization of the fabricated nanofiber was performed utilizing Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction instruments. Effective parameters on the extraction efficiency of the analytes including sample pH, ionic strength, sample flow rate and number of cycles, type, volume, and flow rate of desorption solvent were optimized by one-variable-at-a-time method. Under optimized conditions, the limits of detection were 0.03 and 0.07μg L-1 for diazinon and chlorpyrifos, respectively. This method showed wide linearity in the range 0.10-1000μg L-1 for diazinon and 0.25-1000μg L-1 for chlorpyrifos with R2 > 0.996. The intra- and inter-day precisions (RSD%, n = 3) were ≤ 6.4% and ≤ 7.7%, respectively. Also, RSD% values less than 11.1% were obtained for screw-to-screw reproducibility. The applicability of the method for the extraction and determination of the analytes in complex agricultural environments such as cabbage, potato, tomato, cucumber, and beetroot was investigated. The results led to acceptable relative recoveries in the range 81.0-108.2%.

Application of a magnetic solid-phase extraction method using a novel magnetic metal organic framework nanocomposite for extraction of malathion and diazinon pesticides from environmental water samples

Herein, a magnetic solid-phase extraction (MSPE) method using a synthesized magnetic metal-organic framework composite (Cu-MOF@Fe3O4@SiO2) was applied for the extraction of two well-known organophosphorus pesticides (Malathion and Diazinon) in several environmental water samples. After the extraction, the mentioned target analytes were measured by HPLC-UV. Under the optimal conditions obtained, acceptable linearity was observed within the concentration ranges of 10.0–500.0, and 5.0–500.0 μg/L for malathion and diazinon, respectively. The respective limits of quantification (LOQs) were determined to be 10.0 and 5.0 μg/L for malathion and diazinon. Besides, the MSPE method was successfully implemented to determine the two targets in tap water, surface water, well water, and treated waste water samples with the recoveries varying from 84.0 to 105.5 % (RSDs = 3.8–9.6 %). The obtained results indicated that the combined MOF-based MSPE/HPLC-UV method is of several valuable analytical features, such as high sensitivity, good precision, and the ease of operation and it is practically effective for the extraction and determination of organophosphorus pesticides in various water samples.

Synthesis of oil palm empty fruit bunch-based magnetic-carboxymethyl cellulose nanofiber composite for magnetic solid-phase extraction of organophosphorus pesticides in environmental water samples

This study investigated the development of a magnetic-carboxymethyl cellulose nanofiber (Fe3O4-cmCNF) composite from oil palm empty fruit bunch (OPEFB) as a promising adsorbent for the determination of organophosphorus pesticides (OPPs) in water samples via the magnetic solid-phase extraction (MSPE). The Fe3O4-cmCNF was prepared via the alkaline method and surface-modified using the carboxymethylation and sol–gel technique. The physicochemical characteristics of the Fe3O4-cmCNF were evaluated via FT-IR, VSM, SEM, TEM, XRD, TGA, and BET analysis. Diazinon, fenitrothion, and malathion were selected as the model analytes to examine the feasibility and performance of the Fe3O4-cmCNF-based MSPE to detect OPPs in real environmental water samples using gas chromatography-micro-electron capture detector (GC-µECD). Experimental parameters that affected the extraction efficiency were optimized, including the type and amount of adsorbent, extraction time, pH, type of elution solvent, and ionic strength. Based on the results, the prepared adsorbent showed a high affinity towards OPPs through hydrogen bonding as well as hydrophobic and electrostatic interaction. Under optimum conditions, the linear calibration curves were achieved for diazinon, fenitrothion, and malathion with a concentration range of 0.1–200 ng mL−1 and a suitable determination coefficient (r2) between 0.9962 and 0.9995. Furthermore, acceptable intra- and inter-day precisions were obtained between the range 1.7–4.9 % and 2.0–14.0 %, respectively. The LOD for diazinon, fenitrothion, and malathion was determined at 0.03 ng mL−1, with a satisfactory relative recovery range of 81.8–119.6 %. OPPs residues were detected in river water (0.27–0.39 ng mL−1) and wastewater (0.41–1.31 ng mL−1), indicating that the Fe3O4-cmCNF is a suitable composite for the determination of OPPs in real samples.

Determination of Organophosphorus Pesticides (or Herbicides) in Soybean by Gas Chromatography (or High Performance Liquid Chromatography)

Determination of Organophosphorus Pesticides (or Herbicides) in Soybean by Gas Chromatography (or High Performance Liquid Chromatography)

Ultrasound-enhanced air-assisted liquid-liquid microextraction for the UPLC determination of organophosphorus pesticides in river water

Organophosphorus pesticide (OPP) residues in environment are harmful to ecosystem and human health. In this study, an ultrasound-enhanced air-assisted liquid–liquid microextraction (UE-AA-LLME) method was developed for ultra-high performance liquid chromatography (UPLC) determination of OPPs in water samples. The UE-AA-LLME was performed in a 1.5-mL centrifuge tube under ultrasound condition by sucking in and pushing out the mixture of aqueous solution and extraction solvent using a 2-mL syringe. After centrifugation, the sediment layer was collected and analyzed by UPLC. The parameters affecting the extraction efficiency including the type and volume of extraction solvent, pH, and extraction cycles were optimized. Under the optimized conditions, the limit of detection (LOD) of target OPPs ranged from 0.04 to 0.15 μg/L, and good linearities were acquired with correlation coefficients higher than 0.9927. The recoveries of target OPPs were evaluated to be 75.4–112.6 %, with relative standard deviations (RSDs) lower than 14.9 %. The proposed UE-AA-LLME method was successfully employed for the UPLC determination of OPPs in an urban river of Hangzhou, China. The results revealed that six OPPs were detected in the river waters at the levels of 0.06–0.54 μg/L, and the levels of OPP residues in autumn were higher than those in winter. The risk assessment suggested that there was no human health risk of OPP residues in the river water for adult and child by ingestion pathway.

Novel colorimetric aptasensor based on MOF-derived materials and its applications for organophosphorus pesticides determination

For the visual detection of four organophosphorus pesticides (OPs), a colorimetric aptasensor was developed based on aptamer-mediated bimetallic metal-organic frameworks (MOFs) nano-polymers. Fe-Co magnetic nanoparticles (MNPs) and Fe-N-C nanozymes were prepared based on pyrolytic reaction, and were labeled with broad spectrum aptamers and complementary chains of organophosphorus pesticides respectively. The hybridization of aptamers and complementary chains led to the formation of nano-polymers. In the presence of target pesticides, they competed with complementary chains for aptamers on Fe-Co MNPs, resulting in a large number of Fe-N-C nanozymes signal labels being released into the supernatant. Fe-N-C nanozymes showed similar activity to peroxidase and catalyzed the 3,3′,5,5′-tetramethylbenzidine-hydrogen peroxide (TMB-H2O2) color system to turn the solution blue-green under mild conditions. The magnetic probes had good selectivity and sensitivity, and were easily separated by magnetic absorption. The sensor functioned well under optimal conditions, demonstrating good stability and specificity for four pesticides: phorate, profenofos, isocarbophos and omethoate, and the detection limits of four pesticides were as low as 0.16 ng/mL, 0.16 ng/mL, 0.03 ng/mL and 1.6 ng/mL respectively, and the recovery rate of OPs residue in vegetable samples was satisfactory. The work described here provided a simple, rapid and sensitive way to construct a biosensor.

Evaluation of green silicone surfactant-based vortex assisted dispersive liquid-liquid microextraction for sample preparation of organophosphorus pesticide residues in honey and fruit sample.

A vortex-assisted surfactant enhanced emulsification liquid-liquid microextraction based on non-ionic silicone surfactant was successfully developed for the determination of organophosphorus pesticides in food samples coupled to gas chromatography-mass spectrometry. A new type of non-ionic silicone surfactant composed of polysiloxane chains was employed as a green emulsifier to facilitate the emulsification of extraction solvent into the sample matrix, thereby intensifying the mass transfer of target analytes into the organic phase. The variables that affect the extraction were systematically optimized: 80 μl of hexane and 0.5% (v/v) of silicone surfactant were used as extraction solvent and surfactant respectively, the solution was mixed well under vortex agitation for 1 min with the addition of 4% (w/v) sodium sulfate. Under optimum conditions, the linearity of the method was obtained in the range of 0.1-200 μg/kg with a good coefficient of determination varying from 0.9986 to 0.9996. The limit of detection and the limit of quantitation were between 0.008-0.1 and 0.02-0.3 μg/kg, respectively. Application of the proposed method to real samples gave satisfactory recovery values (80%-118%) for the target analytes. The suggested approach has also proven to be convenient, expeditious, and environmentally benign.

Development of a nanocopper-decorated laser-scribed sensor for organophosphorus pesticide monitoring in aqueous samples

Organophosphorus pesticides are widely used in industrial agriculture and have been associated with water pollution and negative impacts on local ecosystems and communities. There is a need for testing technologies to detect the presence of pesticide residues in water sources, especially in developing countries where access to standard laboratory methods is cost prohibitive. Herein, we outline the development of a facile electrochemical sensor for amperometric determination of organophosphorus pesticides in environmental water samples. A three-electrode system was fabricated via UV laser-inscribing on a polyimide film. The working electrode was functionalized with copper nanoparticles with affinity toward organophosphate compounds. The sensor showed a limit of detection (LOD) of 3.42 ± 1.69 µM for glyphosate, 7.28 ± 1.20 µM for glufosinate, and 17.78 ± 7.68 µM for aminomethylphosphonic acid (AMPA). Sensitivity was highest for glyphosate (145.52 ± 36.73 nA⋅µM−1⋅cm−2) followed by glufosinate (56.98 ± 10.87 nA⋅µM−1⋅cm−2), and AMPA (30.92 ± 8.51 nA⋅µM−1⋅cm−2). The response of the sensor is not significantly affected by the presence of several ions and organic molecules commonly present in natural water samples. The developed sensor shows promising potential for facilitating environmental monitoring of organophosphorus pesticide residues, which is a current need in several parts of the world.Graphical

Matrix‐induced sugaring‐out liquid‐liquid microextraction coupled with high‐performance liquid chromatography for the determination of organophosphorus pesticides in fruit jams

AbstractA rapid and easy analytical method for the determination of organophosphorus pesticides (fenitrothion, phosalone, profenofos, and chlorpyrifos) in fruit jams was developed using sugaring‐out liquid‐liquid microextraction followed by high‐performance liquid chromatography with ultraviolet detection. Acetonitrile was the only chemical used in the sample pretreatment step. The high sugar content of the sample matrix highly accelerated the extraction process as it simply triggered phase separation. The optimized sample treatment involved mixing 600 μl of ACN/water mixture (50/50%, v/v) with 1 g of jam sample, shaking for 0.5 min at 2500 rpm, and then centrifuging the sample for 5 min at 2500 × g. Under the optimal conditions, the extraction recoveries in the range of 81%–89% were achieved for the analytes. Good linearity in a range of 50–5000 μg/kg (r2 ≥ 0.9992) and limits of detection less than 25 μg/kg were obtained. Recovery assays for spiked commercial jams made from cherry, strawberry, blackberry, apricot, and blueberry provided recoveries from 89% to 107%.

Zr-based metal–organic framework incorporated polystyrene nanocomposite as a novel sorbent for ultrasound assisted-thin film microextraction of organophosphorus pesticides from complex samples

In this work, a novel ultrasound assisted-thin film microextraction (USA-TFME) method has been developed to determine organophosphorus pesticides (OPPs) in some fruits and vegetables samples followed by gas chromatography. In this regards, a novel nanocomposite (NC) was prepared by incorporation of zirconium-based metal–organic framework (MOF) into polystyrene (UiO-66/PS) and used as an efficient thin film. The effect of MOF doping level into UiO-66/PS NC and also the effective parameters influencing the TFME method has been studied. Based on the method validation, limits of detection were in the range of 1.5 to 3 µg kg−1. The intra-day precision, inter-day precision and inter-sorbent precision were in the range of 5.1 to 7.2, 5.3 to 10.2 and 4.6 to 7.3 %, respectively. The developed method was prosperously applied for determination of OPPs in some fruit and vegetable samples, leading to the acceptable relative recoveries in the range of 87.8% to 96.3%.

Thermal-controlled active sensor module using enzyme-regulated UiO-66-NH2/MnO2 fluorescence probe for total organophosphorus pesticide determination

An enzyme-regulated UiO-66-NH2/MnO2 fluorescence sensor, fully functionalized with spectrometric capacities, is developed for budget-friendly total organophosphorus pesticides (OPs) determination. The fluorescence probe, UiO-66-NH2/MnO2, is hydrothermally synthesized and morphologically examined. A specialized enzyme-catalyzed reaction, which can be gradually inhibited by OPs, is designed with participations of alkaline phosphatase (ALP) and sodium L-ascorbyl-2-phosphate (AAP). The reaction product of ascorbic acid (AA) decomposes MnO2 and restores UiO-66-NH2 fluorescence, establishing a relationship between OPs level and fluorescence intensity. Interactions among UiO-66-NH2, MnO2, OPs, and AA are clarified. Stepwise optimizations are performed to the UiO-66-NH2/MnO2 probe, ensuring considerable advantages as OPs affinity and fluorescence quenching behavior over rival nanomaterials. Analytical advances are magnified by fabricating an active sensor module, with self-acting thermal regulation for optimal enzyme activity. Under 4 and 20 °C environment, regulation period is less than 40 and 100 s. In total OPs determination for laboratorial and real-vegetable samples, this method exhibits uniform and log-linear responses to common species of OPs in a range as 1.0 × 10−7~10 mg L−1, and limit of detection is established as 8.9 × 10−8 mg L−1. Proposed readouts are validated with certified HPLC and recovery test. Relative errors and recovery rates are found as 2.7–6.4% and 95.8–102.6%, respectively.

Ultra-sensitive acetylcholinesterase biosensor based on leaching Al42Cu40Fe16 quasicrystal modified by MWCNTs-COOH for the determination of organophosphorus pesticide

The icosahedral Al-Cu-Fe quasicrystal (QC) with excellent electrochemical performance is firstly employed to design outstanding electrochemical acetylcholinesterase (AChE) biosensor to detect organophosphorus pesticides (OPs). The Al42Cu40Fe16 QC is treated via leaching in NaOH solution, followed by coating with MWCNTs-COOH, exhibiting excellent catalytic activity, electrical conductivity and biocompatibility. This innovative electrochemical sensing platform based on the leaching Al42Cu40Fe16 QC@ MWCNTs-COOH (LQC@CNT) can be availed to detect acephatemet in the range of 10-12 M to 10-6 M with a detection limit of 1.054 × 10-13 M (S/N = 3). Meanwhile,this modified material improves the affinity between AChE and ATCl, which is proven by the low Michaelis-Menten constant (Km)of 80 μM. This work provides innovative applicability of leaching Al42Cu40Fe16 QC nanomaterials for the excellent detection of OPs in the biosensing area.

A novel electrochemical sensing platform based on the esterase extracted from kidney bean for high-sensitivity determination of organophosphorus pesticides.

Similar to acetylcholinesterase, the activity of plant-derived esterase can also be inhibited by organophosphorus pesticides. Therefore, an electrochemical sensing platform using kidney bean esterase as a new detection enzyme was proposed for the highly sensitive determination of organophosphorus pesticides. Purified kidney bean esterase was obtained by an efficient and economical aqueous two-phase extraction method. Carboxylated graphene/carbon nanotube composites (cCNTs–cGR) and Au nanoparticles were used to provide a biocompatible environment to immobilize kidney bean esterase and also accelerate electron transport between the analyte and the electrode surface. Due to the good synergistic electrocatalytic effects of these nanomaterials, the biosensor exhibited an amplified electrocatalytic response to the oxidation of α-naphthalenol, which makes the sensor more sensitive. Based on the inhibitory effect of trichlorfon on kidney bean esterase activity, high sensitivity and low-cost detection of trichlorfon was achieved. Under optimum conditions, the inhibition of trichlorfon is proportional to its concentration in the range of 5 to 150 ng L−1 and 150 ng L−1 to 700 ng L−1 with an ultra-low detection limit of 3 ng L−1. Moreover, the validity of the prepared biosensor was verified by analyzing several actual agricultural products (cabbage and rice) with satisfactory recoveries ranging from 94.05% to 106.76%, indicating that kidney bean esterase is a promising enzyme source for the analysis of organophosphorus pesticides in food samples.

GNP/Al-MOF nanocomposite as an efficient fiber coating of headspace solid-phase micro-extraction for the determination of organophosphorus pesticides in food samples.

Thesynthesis and utilization of a high porous nanocomposite comprising MIL-53(Al) metal-organic framework (Al-MOF) and graphene nanopowder (GNP) is reportedas a fiber coating for headspace solid-phase micro-extraction (HS-SPME) of selected organophosphorus pesticides (OPPs) from apple, potato, grape juice, tomato, and river water. The adsorbed OPPs on the coated fiber were subsequently determined using GC-MS. Several parameters affecting the efficiency of extraction including time and temperature of extraction, desorption condition of extracted analytes, pH and agitation of sample solution, and salt concentration were investigated. The optimum extraction condition was achieved at 70°C with an extraction time of 40min, pH = 4-8, and NaCl concentration of 6.0% (w/v). The best condition of desorption wereobserved at280°C for 2.0min under a flow of helium gas in the GC inlet. Under optimal conditions, the detection limits ranged from 0.2 to 1.5ngg-1 and the linear ranges between 0.8 and 600ngg-1. The proposed method showed very good repeatability with RSD values ranging from 4.5 to 7.3% (n = 5). The relative recoveries were between 88% and 109% at the spiked level of 25.0ngg-1 for the tomato sample. The fabricated fiber exhibited good enrichment factor (62-195) at optimum condition of HS-SPME. The applied HS-SPME technique is facile, fast, and inexpensive. The thermally stable GNP/Al-MOF exhibited a high sensitivity toward OPPs. So, this nanocomposite can be considered as a sorbent for the micro-extraction of other pesticides in food.

Determination of organophosphorus pesticides based on graphene oxide aerogel solid phase extraction column

以氧化石墨烯气凝胶三维纳米材料作为固相萃取的吸附剂,结合高效液相色谱,对食品中的有机磷农药(辛硫磷、双硫磷、倍硫磷、杀螟硫磷)进行检测分析。首先,利用冷冻干燥的方式制备得到氧化石墨烯气凝胶,通过扫描电镜、红外光谱、比表面积吸附等一系列的实验手段对其形貌及物理特性进行了表征,证明其成功合成。从扫描电镜中可见石墨烯的层状褶皱结构,其表面积为740.51 m2/g。然后,将氧化石墨烯气凝胶直接填充于固相萃取柱中,在未借助任何硅胶等基体的条件下进行萃取研究;通过单因素实验,系统研究了萃取和洗脱条件对有机磷农药萃取回收率的影响。结果显示,在上样体积15 mL、样品溶液pH值4、上样速率1.0 mL/min、洗脱剂1.0 mL乙腈的条件下萃取回收率最高。与商用的萃取材料进行比较,包括碳十八硅胶柱(C18)、阴离子交换柱(SAX)、氨基柱(-NH2)和硅酸镁柱(Florisil),氧化石墨烯气凝胶填充的固相萃取柱的萃取回收率有明显提高。实验考察了氧化石墨烯气凝胶直接填充的萃取柱的寿命,结果显示该萃取柱可以重复使用15次,可见解决了分散无基体支撑的石墨烯纳米片容易破碎、堵塞筛板的问题。与液相色谱联用建立分析方法,4种有机磷农药的线性范围较宽,辛硫磷、双硫磷和倍硫磷的线性范围为1~200 μg/L,杀螟硫磷的线性范围为2~200 μg/L,线性拟合良好(线性相关系数r2≥0.9949),检出限为0.2~0.5 μg/L,满足于我国和其他国家限定标准的检测。将该方法应用于实际样品,在苹果皮中未检测到有机磷农药,对其进行加标,回收率为70.5%~93.6%,相对标准偏差≤10.4%。

Enzyme-Catalyzed Total Organophosphorus Pesticide Determination Using Uio-66-Nh2/Mno2 as Fluorescence Couple on Flexibly-Fabricated Active Sensor Module

Enzyme-Catalyzed Total Organophosphorus Pesticide Determination Using Uio-66-Nh2/Mno2 as Fluorescence Couple on Flexibly-Fabricated Active Sensor Module

Novel Colorimetric Aptasensor Based on Mof-Derived Materials and its Applications for Organophosphorus Pesticides Determination

Novel Colorimetric Aptasensor Based on Mof-Derived Materials and its Applications for Organophosphorus Pesticides Determination

Determination of Organophosphorus Pesticides in Vegetables and Fruit by an Indirect Competitive Enzyme-Linked Immunosorbent Assay (ic-ELISA) and a Lateral-Flow Immunochromatographic (LFIC) Strip Assay

Residues of pesticides in agricultural by-products may cause harm to human health. An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and a competitive form of lateral-flow immunochromatographic (LFIC) strip were developed for the determination of methyl parathion and triazophos in agricultural by-products. In the optimized system for ic-ELISA, the limits of detection (LODs) for methyl parathion and triazophos were 1.39 and 1.94 ng/mL. The linear ranges for methyl parathion and triazophos were from 7.90 to 200 ng/mL and 4.47 to 170.19 ng/mL. The recoveries from agricultural by-products ranged from 84.16 to 106.96% and the coefficients of variation were from 0.77 to 6.45%. In the optimized LFIC system, good linearity was obtained for methyl parathion and triazophos between 5 and 200 ng/mL. The LODs of the CG-LFIC strip for methyl parathion and triazophos were 2.17 and 4.21 ng/mL. The coefficients of variation of the test strip were from 0.73 to 8.34%. Pears, apples, cucumbers, and lettuces spiked with methyl parathion and triazophos were employed to characterize matrix effects using the LFIC strip. The ic-ELISA and LFIC strip were simple and practical for the rapid determination of organophosphorus pesticides in agricultural by-products. Furthermore, the LFIC strip was suitable for on-site testing and rapid screening.