Determination of Chlorophenoxy Acid Herbicides in Water Samples by Suspended Liquid-Phase Microextraction�CLiquid Chromatography

In this study, directly suspended liquid-phase microextraction was investigated for the extraction and determination of five chlorophenoxy acid herbicides in water samples. The optimized parameters for extraction of chlorophenoxy acid herbicides were 1 M HCl concentration in sample solution, solution temperature 20 °C, 45-min extraction time, 1,000 rpm stirring rate, 25 ??L extracting solvent volume and without NaCl addition. Under the optimum conditions, the enrichment factor ranged from 192 to 390. Calibration curves yielded good linearity (R ² > 0.999) and the linear range was 5.0?C500.0 ??g L^?1, limit of detection was 0.3?C0.4 ??g L^?1 and limit of quantification was 1?C2 ??g L^?1 for analytes and the relative standard deviations were in the range of 3?C10% (n = 3). Finally, the proposed method was successfully applied to the quantification of five chlorophenoxy acid herbicides in water samples and recovery was in the range of 74?C110%.     

Determination of Triazine Herbicides and Diuron in Mud from Olive Washing Devices and Soils Using Gas Chromatography with Selective Detectors

Abstract

In the present work, a method for the simultaneous determination of five herbicides, diuron, simazine, atrazine, terbuthylazine and terbutryn by GC‐electron capture detection (ECD) and GC‐thermoionic specific detector (TSD) in soil and mud samples (from olives washing devices) has been developed. Extraction of the herbicides from soil samples was carried out by liquid–solid extraction with ciclohexane/acetone under sonication. In addition, a clean‐up step by solid phase extraction (SPE) using alumina was necessary for mud samples to remove fat residues in the extracts. Spiked soil standards were used for calibration. Limit of detection (LOD) values ranged between 0.2–1.4 ng g^?1 and limit of quantitation (LOQ) between 1.4–2.0 ng g^?1. The precision of the method was satisfactory for all the herbicides analyzed, with RSD values ranging between 7.5%–32.3% and 8.5%–17.8% for 10 and 100 ng g^?1 spiking levels, respectively. The accuracy of the method was checked at three spiking levels (10, 50, and 100 ng g^?1) with recovery values ranging from 74.2%–129.1%. In the case of mud samples, mean recovery values (100 ng g^?1 spiking level) were acceptable for diuron (69.5%) and more satisfactory in the case of triazine herbicides (81.0%–123.0%). Diuron and terbuthylazine were the herbicides most frequently detected in the analyzed samples.     

Determination of five polar herbicides in water samples by ionic liquid dispersive liquid-phase microextraction

A simple, rapid and efficient ionic liquid based on dispersive liquid-phase microextraction (IL-DLPME) method was developed for the determination of three triazine and two phenylurea herbicides in water samples. IL (1-hexyl-3-methylimidazolium hexafluorophosphate [C₆MIM][PF₆]) that dispersed completely into the water solution under controlled temperature was used as the extraction solvent. The analytes were easily concentrated into the ionic liquid phase. This technique combined the process of extraction and concentration of the analytes into one step and avoided use of the more common, toxic organic solvents. The factors affecting the extraction efficiency such as the IL volume, sample pH, extraction time, centrifugal time, dissoluble temperature and ionic strength were optimized. The extracts were analyzed by high-performance liquid chromatography (HPLC) coupled with diode array detector (DAD). Under the optimized conditions, recoveries (50.5–109.1%) were obtained for the target analytes in water samples. The calibration curves were linear and the correlation coefficient ranged from 0.9947 to 0.9973 in the concentration levels of 5–100 μg L^?1. The relative standard deviations (RSDs, n?=?5) were 6.80–10.78%. The limit of detections (LODs) for the five polar herbicides were between 0.46 μg L^?1 and 0.89 μg L^?1.     

Multiwalled Carbon Nanotubes as SPE Adsorbents for Simultaneous Determination of Seven Sulfonylurea Herbicides in Environmental Water by LC–MS–MS

An effective and rapid method was developed for simultaneous determination of seven sulfonylurea herbicides in environmental water using multiwalled carbon nanotubes as solid-phase extraction sorbent coupled with liquid chromatography–tandem mass spectrometry. Important parameters influencing the extraction efficiency such as pH of the sample solution, flow rate of sample loading, the eluent and its volume were optimized. Under optimum conditions, good linearity was obtained for all herbicides (r ² > 0.99) over the range of 0.05–5,000 ng L^?1, and precisions (RSD) for nine replicate measurements of a standard mixture of 200 ng L^?1 were 1.9–7.4%. The limits of detection and quantification were 0.01–0.20 and 0.05–1.00 ng L^?1, respectively. The proposed method was successfully applied to the analysis of tap water, spring water, ground water and well water, and mean recoveries for seven analytes at three spiked concentration levels were from 81.5 to 110.5% with RSDs between 0.3 and 7.0%. The results showed that the established method has wide application to analyze sulfonylurea herbicides at trace level in water.     

Magnetic molecular imprint-based extraction of sulfonylurea herbicides and their determination by capillary liquid chromatography

We have developed a simple method for the extraction of sulfonylurea herbicides (SUHs) from environmental water samples. It is based on a magnetic molecular imprint (MMIP) as a sorbent. The MMIP was prepared using metsulfuron-methyl as the template molecule, methacrylic acid as the functional monomer, trimethylolpropane trimethacrylate as the cross-linking agent, and magnetite as the magnetic component. Extraction can be carried out by blending and stirring water sample, extraction solvent and MMIP. Once the extraction is completed, the MMIP containing the SUHs can be separated from the sample matrix with a magnet. The SUHs desorbed from the polymers were then quantified by capillary liquid chromatography with diode array detection. The limits of quantification are in the range of 0.08 to 0.1 ng?mL^?1. Repeatabilities of peak areas and retention times range from 2.9 % to 4.0 % and from 0.1 % to 0.3 %, respectively. The method was successfully applied to the determination of the SUHs bensulfuron-methyl, metsulfuronmethyl, pyrazosulfuron-methyl, thifensulfuron-methyl, and triasulfuron in waste water samples. Recoveries range from 94.3 % to 102.3 %.

Rapid Multi-Residue Analysis of Herbicides with Endocrine-Disrupting Properties in Environmental Water Samples Using Ultrasound-Assisted Dispersive Liquid–Liquid Microextraction and Gas Chromatography–Mass Spectrometry

A highly efficient ultrasonic-assisted dispersive liquid–liquid microextraction (UA-DLLME) procedure coupled with gas chromatography–mass spectrometry was developed for simultaneous analysis of multiclass herbicides with endocrine-disrupting properties in environmental water samples. The parameters affecting the method’s extraction efficiency, such as the types and volumes of the extractant and dispersive solvents, sample pH, and salt concentration, were systematically optimized by response surface methodology based on central composite design to achieve excellent recoveries for multiclass herbicides. The final UA-DLLME protocol involved 115.6 µL of chloroform (extractant), 861.5 µL of ethanol (dispersive solvent), 5.0 mL of water samples, pH 10.0, and 4.3% NaCl solution. The performance of the developed UA-DLLME was compared with that of conventional solid-phase extraction (SPE). Under optimal extraction conditions, UA-DLLME exhibited a higher enrichment factor and greater sensitivity than SPE, with limits of detection and limits of quantification of 0.004–0.024 and 0.013–0.079 µg L^?1, respectively, for seawater samples. The accuracy and precision of UA-DLLME were satisfactory for seawater samples spiked at three levels (0.2, 2.5, and 5.0 µg L^?1). Average recoveries ranging from 82.3 to 101.8% were achieved, with relative standard deviations lower than 12.8%. The proposed analytical method was successfully applied to the simultaneous determination and quantification of 17 herbicides in environmental river and seawater samples.     

Determination of twelve herbicides in tobacco by a combination of solid–liquid–solid dispersive extraction using multi-walled carbon nanotubes, dispersive liquid-liquid micro-extraction, and detection by GC with triple quadrupole mass spectrometry

We report on a method for the determination of twelve herbicides using solid–liquid–solid dispersive extraction (SLSDE), followed by dispersive liquid-liquid micro-extraction (DLLME) and quantitation by gas chromatography with triple quadrupole mass spectrometric detection. SLSDE was applied to the extraction of herbicides from tobacco samples using multi-walled carbon nanotubes (MWCNTs) as clean-up adsorbents. The effect of the quantity of MWCNTs on SLSDE, and of type and volume of extraction and disperser solvents and of salt effect on DLLME were optimized. Good linearity is obtained in the 5.0 - 500 μg kg^?1 concentration range, with regression coefficients of >0.99. Intra-day and inter-day repeatability, expressed as relative standard deviations, are between 3 and 9 %. The recoveries in case of herbicide-spiked tobacco at concentration levels of 20.0, 50.0 and 100.0 g kg^?1 ranged from 79 to 105 %, and LODs are between 1.5 and 6.1 μg kg^?1. All the tobacco samples were found to contain butralin and pendimethalin at levels ranging from 15.8 to 500.0 μg kg^?1.

LC Determination of Trace Amounts of Phenoxyacetic Acid Herbicides in Water after Dispersive Liquid–Liquid Microextraction

Dispersive liquid–liquid microextraction (DLLME) for extraction and preconcentration of phenoxyacetic acid herbicides in water samples is described. After adjusting the pH to 1.5, the sample was extracted in the presence of 10% w/v sodium chloride by injecting 1 mL acetone as disperser solvent containing 25 μL of chlorobenzene as extraction solvent. The effect of parameters, such as the nature and amount of extraction and disperser solvents, ionic strength of the sample, pH, temperature and extraction time were optimized. DLLME was followed by LC for the determination of 2,4-dichlorophenoxyacetic acid and 4-chloro-2-methyl phenoxyacetic acid. The method had good linearity and a wide linear dynamic range (0.5–750 μg L^?1) with a detection limit of 0.16 μg L^?1 for both the PAAs, making it suitable for their determination in water samples.     

Simultaneous Determination of 12 Sulfonylurea Herbicides in Drinking Water after SPE by LC-DAD

A liquid chromatographic method (LC) with diode array detection (DAD) for the routine screening and quantification of highly applicated polar herbicides in drinking water samples was developed. The investigated herbicides consisted of 12 sulfonylurea herbicides (amidosulfuron, flazasulfuron, foramsulfuron, iodosulfuron-methyl Na, mesosulfuron-methyl, metsulfuron-methyl, nicosulfuron, prosulfuron, thifensulfuron-methyl, triasulfuron and tritosulfuron) together with 6 polar pesticides of relevance (atrazine, desethylatrazine, desisopropylatrazine, chlortoluron, diuron, fluoxypyr). The herbicides were extracted and concentrated by off-line solid-phase extraction and subsequently eluates were analyzed by LC-DAD. Recoveries obtained from fortified water samples at 100 ng L^?1 were in the range of 84–107% with RSD’s <20%. The limit of detection varied from 2 to 16 ng L^?1.     

A new method for the determination of low-level actinium-227 in geological samples

We developed a new method for the determination of ²²⁷Ac in geological samples. The method uses extraction chromatographic techniques and alpha-spectrometry and is applicable for a range of natural matrices. Here we report on the procedure and results of the analysis of water (fresh and seawater) and rock samples. Water samples were acidified and rock samples underwent total dissolution via acid leaching. A DGA (N,N,N′,N′-tetra-n-octyldiglycolamide) extraction chromatographic column was used for the separation of actinium. The actinium fraction was prepared for alpha spectrometric measurement via cerium fluoride micro-precipitation. Recoveries of actinium in water samples were 80 ± 8 % (number of analyses n = 14) and in rock samples 70 ± 12 % (n = 30). The minimum detectable activities (MDA) were 0.017–0.5 Bq kg^?1 for both matrices. Rock sample ²²⁷Ac activities ranged from 0.17 to 8.3 Bq kg^?1 and water sample activities ranged from below MDA values to 14 Bq kg^?1of ²²⁷Ac. From the analysis of several standard rock and water samples with the method we found very good agreement between our results and certified values.     

Hollow fiber membrane supported thin liquid film extraction for determination of trace phenoxy acid herbicides and phenols in environmental water samples

Traces of phenoxy acid herbicides and phenols were determined in environmental water samples by high performance liquid chromatography (HPLC) coupled to thin liquid film extraction (TLFE). A TLFE sampling device was prepared by dipping pieces of a polypropylene microporous hollow fiber membrane into dihexyl ether (containing 10% tri-n-octylphosphine oxide as carrier) for a few minutes to impregnate the pores of the hollow fiber wall. Extraction of analytes takes place from the outer aqueous phase into the immobilized solvent. After extraction the removal of the organic solvent was accomplished with a few µl of methanol which was used for HPLC analysis. Enrichment factors as high as 446 were obtained for the target compounds. The method provided detection limits as low as 0.4–1.2 µg L^?1, good repeatability (the RSD ranging from 2.1 to 6.3%, n?=?5) and a linear range from 2 to 200 µg L^?1 for the target compounds. Real sample analysis showed recoveries between 84.6% and 112% for all compounds investigated.     

Magnetic solid-phase extraction of sulfonylurea herbicides in environmental water samples by Fe3O4@dioctadecyl dimethyl ammonium chloride@silica magnetic particles

A magnetic solid phase extraction (MSPE) method coupled with high-performance liquid chromatography (HPLC) was proposed for the determination of five sulfonylurea herbicides (bensulfuron-methyl, prosulfuron, pyrazosulfuron-ethyl, chlorimuron-ethyl and triflusulfuron-methyl) in environmental water samples. The magnetic adsorbent was prepared by incorporating Fe₃O₄ nanoparticles and surfactant into a silica matrix according to a sol–gel procedure, which can provide surfactant free extracts during the eluting step to avoid chromatographic interference. The prepared adsorbent was used to extract the sulfonylurea herbicides in several kinds of water samples. The main factors affecting the extraction efficiency, including desorption conditions, extraction time, sample volume, and sample solution pH were optimized. Under the optimum conditions, good linearity was obtained within the range of 0.2–50.0 μg L⁻¹ for all analytes, with correlation coefficients ranging from 0.9993 to 0.9999. The enrichment factors were between 1200 and 1410, and the limits of detection were between 0.078 and 0.10 μg L⁻¹. The proposed method was successfully applied in the analysis of sulfonylurea herbicides in environmental samples (tap, reservoir, river, and rice field). The recoveries of the method ranged between 80.4% and 107.1%. This study reported for the first time the use of MSPE procedure in the preconcentration of sulfonylurea herbicides in environmental samples. The procedure proved to be efficient, environmentally friendly, and fast.     

Magnetic Graphene Nanoparticles for the Preconcentration of Chloroacetanilide Herbicides from Water Samples Prior to Determination by GC-ECD

A highly sensitive method for the determination of the chloroacetanilide herbicides alachlor, acetochlor, pretilachlor, butachlor, and metolachlor in environmental water samples was developed. It is based on solid-phase extraction using magnetic graphene nanocomposite (G-Fe₃O₄) as the adsorbent, followed by gas chromatography with electron capture detection. This novel adsorbent showed a great adsorptive ability toward the analytes. The main experimental parameters such as the amount of G-Fe₃O₄, extraction time, ionic strength, the pH of the sample solution, and desorption conditions were optimized. Under the optimum conditions, the enrichment factors of the method for the analytes were in the range from 649 to 1078. A good linear response was achieved in the range of 0.2–20.0 ng mL^?1, with correlation coefficients (r) varying from 0.9964 to 0.9998. The limits of detection of the method ranged from 0.02 to 0.05 ng mL^?1 and the relative standard deviations were below 4.5%. The method was successfully applied to the determination of the herbicides in environmental water samples. Recoveries of the method for the analytes were in the range of 80.7–105.3%.     

Ionic‐liquid‐functionalized magnetic particles as an adsorbent for the magnetic SPE of sulfonylurea herbicides in environmental water samples

In this paper, a new ionic‐liquid‐functionalized magnetic material was prepared based on the immobilization of an ionic liquid on silica magnetic particles that could be successfully used as an adsorbent for the magnetic SPE of five sulfonylurea herbicides (bensulfuron‐methyl, prosulfuron, pyrazosulfuron‐ethyl, chlorimuron‐ethyl and triflusulfuron‐methyl) from environmental water samples. The main parameters affecting the extraction efficiency such as desorption conditions, sample pH, extraction time and so on, were optimized using the Taguchi method. Good linearities were obtained with correlation coefficients ranging from 0.9992 to 0.9999 in the concentration range of 0.1–50 μg L^?1 and the LODs were 0.053–0.091 μg L^?1. Under the optimum conditions, the enrichment factors of the method were 1155–1380 and the recoveries ranged from 77.8 to 104.4%. The proposed method was reliable and could be applied to the residue analysis of sulfonylurea herbicides in environmental water samples (tap, reservoir and river).     

Mesostructured cellular foam solid‐phase microextraction coating for the highly sensitive recognition of polychlorinated biphenyls in water samples

We herein presented a mesoporous cellular foam solid‐phase microextraction coating that showed highly sensitive recognition for weakly polarity polychlorinated biphenyls in water samples. The mesoporous cellular foam coater fiber was for the first time prepared by a simple sol‐gel method. The main experimental parameters including extraction temperature, extraction time, desorption time, stirring rate, and ionic strength were investigated by high‐efficiency orthogonal array design, a L₁₆ (4⁴) matrix was applied for the identification of optimized extraction parameters, and the optimized method was successfully applied to the analysis of environmental water sample. The novel mesoporous cellular foam coated fibers exhibited sensitive limits of detection (0.07–0.28 µg/L), wide linearity (5–3000 µg/L), and good reproducibility (3.5–8.3% for single fiber, and 4.9–8.7% for fiber‐to‐fiber) for polychlorinated biphenyls. The home‐made coating was successfully used in the analysis of polychlorinated biphenyls in real environmental water samples. These results indicate that the synthesized mesoporous cellular foams are promising materials for adsorption and separation applications in sample pretreatment.     

Graphene oxide reinforced polyamide nanocomposite coated on paper as a novel layered sorbent for microextraction by packed sorbent

ABSTRACT

In this work, a novel layered sorbent for microextraction by packed sorbent (MEPS) was introduced, which has been prepared by coating graphene oxide/polyamide (GO/PA) nanocomposite (NC) onto cellulose paper through solvent exchange method. Scanning electron microscopy (SEM) was applied to investigate the surface characteristic and morphology of PA and GO/PA NC coated on cellulose paper. The prepared MEPS device was used for extraction of organophosphorous pesticides (OPPs) including chlorpyrifos, fenthion, fenithrothion, ethion, edifenphos and phosalone in environmental aqueous samples followed by detection using gas chromatography-flame ionisation detector (GC-FID). Important parameters affecting the MEPS method including pH of sample solution, extraction draw-discard cycles, sorbent layers, desorption solvent volume and desorption draw-eject number were studied and optimised using central composite design (CCD). Based on the method validation, limits of detection (LODs) were in the range of 0.2–1 µg L^?1. The calibration graphs for chlorpyrifos, fenthion and edifenphos are linear in the concentration range of 1 to 500 µg L^?1; for ethion and phosalone are linear in the range of 1–1000 µg L^?1 and for fenithrothion is linear in the range of 3–1000 µg L^?1. The method precision (RSD %) with six replicates determinations was in the range of 3 to 9.4 % and 3.9 to 11.9% for distilled water and spiked river water sample, respectively, at the concentration level of 300 µg L^?1 . The developed method was applied successfully to determine OPP compounds in river, dam and tap water samples; accordingly, the relative recoveries (RR%) were obtained in the range of 77.8 to 113.3%.     

Determination of Triazine Herbicides and Metabolites by Solid Phase Extraction with HPLC Analysis

An efficient solid phase extractive preconcentration/separation method was developed for the trace determination of herbicides in aqueous samples using Amberlite XAD-4 resin as the adsorbent. The retained herbicides were eluted with methanol at a flow rate of 1.0 mL min^?1 and determined by HPLC-DAD (wavelength of 220 nm) using water (pH:4.7, phosphoric acid) and methanol (ratio 35:65) as the mobile phase with a flow rate of 1.0 mL min^?1. Quantitative recoveries of simazine, atrazine and its metabolities were achieved at optimized analysis conditions that included 0.75 g of resin; a pH of 3.0; an eluent volume of 3.0 mL; an eluent flow rate of 1.0 mL min^?1; and a sample flow rate of 4.0 mL min^?1. The limits of detection, preconcentration factor, and linear ranges for the herbicides were 0.084–0.121 µgL^?1, 1000, and 0.5–20 mg L^?1, respectively. The performance of the method was evaluated by analysis of spiked water samples. The recoveries of simazine, atrazine and their metabolities were found to be quantitative (99.6–104.8%) with RSDs of 2.2–4.8% and 2.8–4.7% for intra-day and inter-day precision, respectively. The proposed method was successfully applied for trace determination of studied analytes in waste water, apple juice, and red wine samples.     

On-line Micro Solid-Phase Extraction of Clodinafop Propargyl from Water,Soil and Wheat Samples Using Electrospun Polyamide Nanofibers

An on-line extraction/determination set up was designed for micro solid-phase extraction of clodinafop propargyl from water, soil and wheat samples using electrospun polyamide nanofiber mats. The prepared mats were packed in a stainless steel tube which conveniently acted as a high-performance liquid chromatography injection loop. Influential parameters affecting the extraction efficiency were optimized using a distilled water sample fortified with 25 μg L^?1 of clodinafop propargyl. An enrichment factor of 440 was achieved for clodinafop propargyl indicating the ability of the whole procedure. Under the optimum conditions, the linearity for the analyte was in the range of 6–700 μg L^?1, while a limit of detection and limit of quantification of 2 and 6 μg L^?1 were achieved, respectively. The intra-day and inter-day RSD% at the concentration level of 25 μg L^?1 were 4.6 and 9.3 %, respectively. To investigate the matrix effect, the developed method was applied to the analysis of real water samples including paddy and river waters as well as the wheat and soil samples. The relative recovery percentages for the spiked samples were in the range of 63–95 %.     

Determination of Estrogens in Water Samples by Ionic Liquid-Based Dispersive Liquid-Liquid Microextraction Combined with High Performance Liquid Chromatography

Using 1-hexyl-3-methylimidazolium hexafluorophosphate ([C₆MIM][PF₆]) ionic liquid as extraction solvent, five estrogens including estrone (E₁), 17β-estradiol (E₂), estriol (E₃), 17α -ethynylestradiol (EE₂), and diethylstilbestrol (DES) in water samples were determined by dispersive liquid-liquid microextraction (DLLME) followed by high performance liquid chromatography with a photodiode array detector and a fluorescence detector (HPLC-DAD-FLD). The extraction procedure was induced by the formation of cloudy solution, which was composed of fine drops of [C₆MIM][PF₆] dispersed entirely into the sample solution with the help of a disperser solvent (acetone). Parameters including both extraction and disperser solvents and their volumes, extraction and centrifugal time, sample pH, and salt effect were investigated and optimized. Under the optimized conditions, 110–349 fold enrichment factors of analytes were obtained. The calibration curves were linear in the concentration range of 0.2–100 µg L^?1 for E₂, E₃, and EE₂ detected with FLD, and 1–100 µg L^?1 for E₁ and DES detected with DAD. The correlation coefficient of the calibration curve was between 0.9990 and 0.9997. The limits of detection (LOD, S/N = 3) for the five estrogens were in the range of 0.08–0.5 µg L^?1. The relative standard deviations (RSD) for six replication experiments at the concentration of 5.0 µg L^?1 were ≤5.7%. The proposed method was applied to the analysis of three water samples from different sources (river water, waste water, and sea water). The relative recoveries of spiked water samples are satisfied with 89.3–102.4% and 88.7–105.2% at two different concentration levels of 5.0 and 50.0 µg L^?1, respectively.     

Bamboo Charcoal as Solid-Phase Extraction Adsorbent for the Determination of Organophosphorus Pesticides in Water Samples by High-Performance Liquid Chromatography

In this paper, bamboo charcoal was successfully developed for the solid-phase extraction adsorbent for the determination of six organophosphorus pesticides in water samples. After the bamboo charcoal was pretreated and packed in the solid-phase extraction cartridge, the organophosphorus pesticides in water samples were carried out the solid-phase extraction. To establish a perfect solid-phase extraction procedure, the experimental conditions including the eluent, eluent volume, pH of the sample, flow rate of the sample, and loading volume of the sample were all investigated. When 100 mL water samples in the pH range of 6–7 were loaded with the flow rate of 2.5 mL · min^?1 and then eluted with 10 mL acetonitrile, the proposed extraction method was validated by the recovery, correlation coefficient (R²), repeatability (RSD, n = 7) and LODs, which were 69.6–93.4%, 0.9982–0.9998, 2.9–5.6%, and 0.08–1.04 µg · L^?1, respectively. Furthermore, the analysis of the tap, snow, and river water samples demonstrated the feasibility of the proposed SPE method for real water samples. Based on the aforementioned factors, it could be concluded that bamboo charcoal was a good solid-phase extraction adsorbent, and this proposed solid-phase extraction method was suitable for the effective enrichment and determination of the organophosphorus pesticides in water samples.