A novel honeycomb-like 3D-printed device for rotating-disk sorptive extraction of organochlorine and organophosphorus pesticides from environmental water samples.

In this study, 3D-printing based on fused-deposition modeling (FDM) was employed as simple and cost-effective strategy to fabricate a novel format of rotating-disk sorptive devices. As proof-of-concept, twenty organochlorine and organophosphorus pesticides were determined in water samples through rotating-disk sorptive extraction (RDSE) using honeycomb-like 3D-printed disks followed by gas chromatography coupled to mass spectrometry (GC-MS). The devices that exhibited the best performance were comprised of polyamide + 15 % carbon fiber (PA + 15 % C) with the morphology being evaluated through X-ray microtomography. The optimized extraction conditions consisted of 120 min of extraction using 20 mL of sample at stirring speed of 1100 rpm. Additionally, liquid desorption using 800 µL of acetonitrile for 25 min at stirring speed of 1100 rpm provided the best response. Importantly, the methodology also exhibited high throughput since an extraction/desorption platform that permitted up to fifteen simultaneous extractions was employed. The method was validated, providing coefficients of determination higher than 0.9706 for all analytes; limits of detection (LODs) and limits of quantification (LOQs) ranged from 0.15 to 3.03 µg L-1 and from 0.5 to 10.0 µg L-1, respectively. Intraday precision ranged from 4.01 to 18.73 %, and interday precision varied from 4.83 to 20.00 %. Accuracy was examined through relative recoveries and ranged from 73.29 to 121.51 %. This method was successfully applied to analyze nine groundwater samples from monitoring wells of gas stations in São Paulo. Moreover, the greenness was assessed through AGREEprep metrics, and an overall score of 0.69 was obtained indicating that the method proposed can be considered sustainable.

Phoslactomycins Revisited: Polyketide Tetrahydrofurans and Lactones from an Australian Wasp Nest-Derived Streptomyces sp. CMB-MW079.

Molecular network analysis of Streptomyces sp. CMB-MW079 detected rare phosphorylated natural products. Miniaturized cultivation profiling (MATRIX) established optimal conditions for the production, isolation, and identification of the polyketide δ-lactone phoslactomycin E (1) and new ester homologues, phoslactomycins J and K (2 and 3), as well as unprecedented heterocyclic analogues, the tetrahydrofuran cyclolactomycins A-D (4-7) and γ-lactone isocyclolactomycins A-C (8-10). We propose a biogenetic relationship linking these cometabolites with the known lactomycins A-C which were tentatively identified as minor cometabolites.

Synthesis of metal-organic framework @molecularly imprinted polymer adsorbents for solid phase extraction of organophosphorus pesticides from agricultural products.

The novel core-shell structural zeolitic imidazolate framework-8 @molecularly imprinted polymers were successfully synthesized by surface imprinting technique and used as adsorbents for solid-phase extraction of organophosphorus pesticides. The obtained hybrid composites were characterized by scanning electron microscopy, transmission electron microscopy and Fourier-transform infrared, and their adsorbing and recognition performance were evaluated by binding experiments. The results showed that zeolitic imidazolate framework-8 @molecularly imprinted polymers presented a typically core-shell structure with molecularly imprinted shell (about 50 nm) homogeneously polymerized on the surface of zeolitic imidazolate framework-8 core, and exhibited specific recognition towards organophosphorus pesticides with fast adsorption capacity. The adsorption and desorption conditions including sample loading solvent, sample pH, washing and elution solvent were optimized. Under optimum conditions, the solid-phase extraction based on zeolitic imidazolate framework-8 @molecularly imprinted polymers combined with high liquid chromatography-tandem mass spectrometry method for determining organophosphorus pesticides was established and exhibited good linearity (R2 ≥ 0.9927) in the range of 1-200 µg/L. With spiked at three different concentration levels in agricultural products (cauliflower, radish, pear, muskmelon), the recoveries ranged from 82.5% to 123.0% with relative standard deviations lower than 8.24%. The developed method was sensitive, convenient and efficient. More importantly, this study could provide a promising strategy for designing new adsorbents with extremely fast mass transfer rate for other potential trace contaminants.

Validation and Evaluation of Selected Organic Pollutants in Shrimp and Seawater Samples from the NW Portuguese Coast.

The development of coastal regions has contributed to the intensification of environmental contamination, which can accumulate in aquatic biota, such as shrimps. These crustaceans, besides being delicious and being a good source of nutrients, can also accumulate environmental pollutants. Amongst others, these include organochlorine pesticides (OCPs), organophosphorus pesticides (OPPs), brominated flame retardants (BFRs), polychlorinated biphenyls (PCBs) and synthetic musks (SMs). These pollutants, classified as endocrine disruptors, are related to adverse effects in humans and since one of the major routes of exposition is ingestion, this is a cause for concern regarding their presence in food. The aim of the present study was to quantify the presence of environmental pollutants in shrimp samples and in the water from their habitat along the northwest Portuguese coast. In seawater samples, only two OCPs (lindane and DDD) and one BFR (BTBPE) were detected, and in shrimp samples, one OCP (DDD) and three SMs (HHCB, AHTN and ketone) were found. Bioaccumulation and the risk assessment of dietary exposure of SMs in shrimp samples were investigated. It was observed that all shrimp samples analyzed significantly presented bioaccumulation of the three SMs found. Concentrations of SMs detected in shrimp samples do not present a health risk for the adult Portuguese population.

A fluorinated chitosan-based QuEChERS method for simultaneous determination of 20 organophosphorus pesticide residues in ginseng using GC-MS/MS.

In this study, a new fluorinated methacrylamide (MACF) was synthesized and evaluated as an adsorbent in the dispersive solid-phase extraction for the effective determination and extraction of 20 organophosphorus pesticides (OPPs) from ginseng samples using the QuEChERS (quick, easy, cheap, effective, rugged, safe) method coupled with GC-MS/MS. The properties of MACF were characterized using Fourier-transform infrared spectroscopy, elemental analysis, and high-resolution 19 F NMR. MACF, chitosan, primary and secondary amine, octadecylsilane, graphitized carbon black, Z-Sep, Z-Sep+ , and EMR-Lipid were compared in terms of extraction efficiency. The best results were obtained when MACF was used. Matrix-matched calibration was employed for quantification. All the OPPs exhibited good linearity (r2 > 0.9969) with the concentration at their respective concentration ranges. The limits of detection were 1.5-3.0 µg/kg, and the limits of quantification were 5.0-10.0 µg/kg. The trueness of the 20 pesticides at four spiked levels ranged from 86.1 to 111.1%, and the relative standard deviation was less than 11.3%. The modified QuEChERS method using MACF as the adsorbent was sensitive, reliable, and cost-effective and could be used for the determination of 20 OPP residues in ginseng.

Triphenylphosphonium functionalized Ficus religiosa L. extract loaded nanoparticles improve the mitochondrial function in oxidative stress induced diabetes.

The present study was aimed to enhance the mitochondrial function in oxidative stress-induced diabetes. To achieve this, Ficus religiosa L. extract loaded solid lipid nanoparticles (ETNPs) were prepared and functionalized by using triphenylphosphonium. Developed nanoparticles demonstrated desired quality attributes with sustained release for up to 24 h and excellent storage stability for up to 180 days at 40 ± 2°C and 75 ± 5% relative humidity. In vitro cytotoxicity assessment showed no toxicity of ETNPs. Interestingly, oral administration of ETNPs to diabetic rats demonstrated improved mitochondrial function by normalizing the mitochondrial morphology, intracellular calcium ion concentration, complexes I, II, IV, and V activity, mitochondrial membrane potential, and antioxidant levels. Further, reduction in apoptotic markers viz. cytochrome-C, caspase-3, and caspase-9 was observed following the ETNP treatment. Moreover, significant reduction in blood glucose and glycosylated hemoglobin while significant improvement in plasma insulin was observed as compared to the diabetic group following the treatment with developed formulation. Furthermore, histopathology studies confirmed the safety of the developed formulation and thus, data in hand collectively suggest that proposed strategy can be effectively used to improve the mitochondrial function in oxidative stress-induced diabetes along with better control over blood glucose and glycosylated hemoglobin.

Facile synthesis of covalent organic frameworks functionalized with graphene hydrogel for effectively extracting organophosphorus pesticides from vegetables.

A novel covalent organic framework material (3DGA@COFs), for use as a solid-phase dispersion sorbent, has been synthesized for extracting organophosphorus pesticides (OPs) from vegetables. The prepared 3DGA@COFs material exhibited many advantageous features, including a large specific surface area (127.95 m2/g) and high pore volume (0.0344 cm3/g), which made it an ideal sorbent for sample pretreatment. The experimental conditions affecting extraction performance (adsorbent type, adsorbent amount, reaction time, pH, ionic concentration, and eluent) were optimized systematically. The extracted analytes were detected by HPLC-MS/MS. Under optimized conditions, the proposed method exhibited a wide linear range (0.5-100 µg/L) and low limits of detection (0.01-0.14 µg/L). The recoveries (75.40%-102.13%) satisfied the requirements for a precise detection method. The proposed method was successfully used for determining malathion, triazophos, quinalphos in lettuce, tomato and cucumber samples, thus indicating the potential of using 3DGA@COFs materials for pretreating vegetable samples.

Determination of organophosphorus and synthetic pyrethroid pesticide residues and their variability in large size fruit crops.

BACKGROUND: Variability of pesticide residues in food item plays a key role for the evaluation of consumer food safety. However, variability factors (VFs) derived from the large size fruit crops are still scarce. Therefore, the present work was aimed to quantify pesticide residues and to estimate VFs in large size fruit crops of mango and guava. RESULTS: A total of 140 mango and 130 guava samples from different marketplaces in Bangladesh were collected to estimate the variability of pesticide residues (acephate, diazinon, malathion, fenitrothion, chlorpyrifos, quinalphos, dimethoate and cypermethrin) by in-house validated methods based on modified QuEChERS extraction and gas chromatography coupled with electron capture detector (ECD) and flame thermionic detector (FTD). The method was validated at three fortification levels (0.01, 0.10 and 0.30 mg kg-1 ) and satisfactory recoveries (80-111%) with relative standard deviation (RSDr ) ≤ 13% were achieved. A wide variation of residues was found in the analyzed samples. In the case of mango, the ranges of residues were 0.011-0.314, 0.015-0.04, and 0.05-0.291 mg kg-1 , respectively, for cypermethrin, chlorpyrifos, and dimethoate, while in the case of guava, the ranges were 0.04-0.113, and 0.03-0.290 mg kg-1 , respectively, for cypermethrin and acephate. The average VF for mango was 4.06 and it was 5.70 for guava. CONCLUSION: VFs originating from the marketed samples of mango and guava are reported in this study for the first time. The estimated VFs were higher than the default value of 3, therefore, the default VFs should be reconsidered when more data are obtained regarding large size crops. © 2021 Society of Chemical Industry.

Solvent-assisted dispersive liquid-solid phase extraction of organophosphorus pesticides using a polypyrrole thin film-coated porous composite magnetic sorbent prior to their determination with GC-MS/MS.

A porous composite magnetic sorbent was developed and used as a solid phase for the solvent-assisted preconcentration of organophosphorus pesticides. The hierarchical porous composite sorbent was composed of polypyrrole thin film coated on the surface of porous alginate beads with embedded magnetite nanoparticles. The pores in the alginate hydrogel beads were produced by carbon dioxide bubbles from the reaction of incorporated calcium carbonate with hydrochloric acid. The porous network was filled with dichloromethane to assist extraction. The fabricated porous composite sorbent was characterized and sorbent fabrication and extraction conditions were optimized to obtain the best extraction performance. The developed sorbent was coupled with GC-MS/MS to determine organophosphorus pesticides in fruit juices and vegetable. Under optimized condition, the developed method provided good linear range of 0.03-200 µg L-1 for dichlorvos, malathion, and fenthion, and 0.075-200 µg L-1 for mevinphos, dimethoate, and parathion methyl, respectively. Limits of detection were in the range 0.010 to 0.025 µg L-1. This method exhibited good relative recoveries in the range 84 to 99% and RSDs lower than 8%. The good stability of the sorbent enabled up to eight cycles of reuse.Graphical abstract.

Development of an Atmospheric Pressure Chemical Ionization Interface for GC-MS.

A closed atmospheric pressure chemical ionization (APCI) ion source as interface between a gas chromatograph (GC) and a triple quadrupole mass spectrometer (QqQ-MS) was developed. The influence of different ion source conditions, such as humidity, make-up gas flow, and the position of the GC column, were investigated and determined as main factors to increase sensitivity and repeatability of the system. For a performance test under real conditions, the new APCI ion source was used for the determination of plant protection products in commercially available coffee beans from Vietnam. The ionization behavior was investigated and the majority of the analytes were detected as [MH]+, [M]+∙, or as characteristic fragment ions, which have been assigned to ion source fragmentation. The developed GC-MS methods are based on tandem MS (MS/MS) and revealed for the plant protection products limits of detection (LOD) between 1 and 250 pg on column and relative standard derivations for all compounds < 16%. The used ultrasonic solid-liquid extraction yielded recovery rates of approximately 60 to 100%. Residues of herbicide methyl esters, organophosphorus compounds, and organonitrogen compounds have been detected in the analyzed coffee beans.

Innovations in Extractive Phases for In-Tube Solid-Phase Microextraction Coupled to Miniaturized Liquid Chromatography: A Critical Review.

Over the past years, a great effort has been devoted to the development of new sorbents that can be used to pack or to coat extractive capillaries for in-tube solid-phase microextraction (IT-SPME). Many of those efforts have been focused on the preparation of capillaries for miniaturized liquid chromatography (LC) due to the reduced availability of capillary columns with appropriate dimensions for this kind of system. Moreover, many of the extractive capillaries that have been used for IT-SPME so far are segments of open columns from the gas chromatography (GC) field, but the phase nature and dimensions are very limited. In particular, polar compounds barely interact with stationary GC phases. Capillary GC columns may also be unsuitable when highly selective extractions are needed. In this work, we provide an overview of the extractive capillaries that have been specifically developed for capillary LC (capLC) and nano LC (nanoLC) to enhance the overall performance of the IT-SPME, the chromatographic separation, and the detection. Different monolithic polymers, such as silica C18 and C8 polymers, molecularly imprinted polymers (MIPs), polymers functionalized with antibodies, and polymers reinforced with different types of carbon nanotubes, metal, and metal oxide nanoparticles (including magnetic nanoparticles), and restricted access materials (RAMs) will be presented and critically discussed.

Effective extraction of organophosphorus pesticides using sol-gel based coated stainless steel mesh as novel solid-phase extraction sorbent.

In this study, for the first time, stainless steel meshes coated with poly(ethylene glycol) and carbon nanotubes (PEG-CNT) by sol-gel technique were used as the adsorbent for solid-phase extraction. The coated stainless steel is loaded onto a cartridge and used to isolate and extract organophosphorus pesticides (OPPs) from water and fruit juice samples. Effective extraction parameters such as sample volume, desorption solvent, and desorption solvent volume were studied and investigated. Under optimal conditions, the linearity of the method was obtained in the range of 0.03 to 80 ng mL-1 and also the limits of detection (LODs) of the method were ranged from 0.01 to 0.03 ng mL-1. The repeatability of the method was evaluated at three concentration levels (0.1, 1, and 50 ng mL-1), and the relative standard deviation (RSD%) of the method was obtained in the range of 3.8 to 4.8%. Finally, the proposed method was used to analysis of OPPs in real water and fruit juice samples, with relative recovery in the range of 94.3 to 99.8%.

Quantification of Trace Organophosphorus Pesticides in Environmental Water via Enrichment by Magnetic-Zirconia Nanocomposites and Online Extractive Electrospray Ionization Mass Spectrometry.

A total of 15 representative organophosphorus pesticides (OPPs), a class of water pollutants causing serious global concerns, have been sensitively quantified by internal extractive electrospray ionization mass spectrometry (iEESI-MS) after enrichment with Fe3O4-ZrO2 innovatively synthesized in our lab by a one step coprecipitation method. For the premium enrichment, the amounts of Fe3O4-ZrO2, pH value, adsorption time, type and volume of desorption solvent, and shaking time of desorption were systematically optimized. Under optimized conditions, the proposed method provided low limits of detection (LODs) of 0.14-16.39 ng L-1 with relative standard deviations (RSDs) of less than 8.7%. A wide linear response range of about 4 orders of magnitude was achieved with linear coefficients (R2) of 0.9921-0.9999 for all the analytes tested. The present method also provided good recoveries (85.4-105.9%) with acceptable precision (RSDs < 7.2%) in spiked environmental water samples. Furthermore, multiple analytes including dimethoate, omethoate, etc. were simultaneously detected in a single sample run, which was accomplished within 1 min, resulting in significantly improved analytical throughput for quantitative analysis of bulk amounts of samples. The experimental results demonstrated that Fe3O4-ZrO2-iEESI-MS provided advantages, including high sensitivity, high speed, and reasonable selectivity for the detection of OPPs, showing potential applications in environmental water sample analysis and environmental science.

Screening of chiral shift reagents suitable to generically separate the enantiomers of V-agents by 31P-NMR spectroscopy.

Fourteen amino acids protected at the N-terminal and at their side chains were screened for resolving the enantiomers of V-agents by NMR. While none of the shift reagents tested showed really effective separation in proton NMR, two of them (BOC-Gln(Xan)-OH, 16, and Z-Arg(Z)2-OH), 21, with 16 superior to 21) were found suitable to separate the enantiomers of all V-agent homologues involved in the test by 31P-NMR. Molar ratios investigated were 1:0.5, 1:1, 1:1.5, 1:2, and 1:3 with the V-agent set to 1 throughout the experiments. All these ratios were more or less effective, but 1:3 was found to separate the V-agents the most reliable way. It is postulated that three chiral solvating molecules are then coordinated around the organophosphate: ion pair formation with the amino nitrogen of the V agent side chain, hydrogen bonding provided by the PO unit, and extension of coordination at the phosphorus atom itself. After chiral separation of VX by semi-preparative LC-MS the enantiomers were examined with both configurations of 16 releasing four different 31P NMR peaks which correspond to four different complexes: R-S3, R-R3, S-R3, and S-S3. Comparing these results with literature data it is assumed that (+)-VX corresponds to the RP configuration and (-)-VX to the SP-configuration.

Multifiber solid-phase microextraction using different molecularly imprinted coatings for simultaneous selective extraction and sensitive determination of organophosphorus pesticides.

Three types of molecularly imprinted solid-phase microextraction fibers were fabricated through sol-gel method using diazinon, parathion-methyl, and isocarbophos as templates, respectively, and assembled together to construct a multifiber for analysis of organophosphorus pesticides in complex matrices. The multifiber provided large extraction capacity and high imprinting factor up to 3.89. In contrast, the imprinting factor of a single fiber was around 1.6, and the multi-template imprinted coating showed no selectivity. The multifiber was applied to analyze pesticides in fruits and vegetables. The limits of detection, which ranged from 0.0052 to 0.23 µg/kg, were lower than those obtained by a single molecularly imprinted fiber, and much lower than those reported by other methods. The recoveries of five analytes in spiked apple, cucumber, Chinese cabbage, and cherry tomato samples were 75.1-123.2%. The study shows that the molecularly imprinted multifiber could achieve simultaneous selective extraction and sensitive determination of multiple targets in complex matrices for high-throughput analysis.

Analysis of organophosphorus and pyrethroid pesticides in organic and conventional vegetables using QuEChERS combined with dispersive liquid-liquid microextraction based on the solidification of floating organic droplet.

A simple, sensitive and environmentally-friendly method for determining organophosphorus and pyrethroid pesticides in vegetables was developed to better evaluate the risk of consuming them. The pesticides in vegetables were extracted, purified and concentrated by using the QuEChERS (quick, easy, cheap, effective, rugged and safe method) combined DLLME-SFO (dispersive liquid-liquid microextraction based on solidification of floating organic droplet) techniques. The key parameters were optimized through orthogonal array experimental design and statistical analysis. The linearity of the calibration curves was satisfied in matrix-matched standard solution with R2 ≥ 0.99. The limits of detection and limits of quantification were 0.3-1.5 and 0.9-4.7 µg/kg, respectively. The average recoveries of pesticides were 61.6-119.4% with relative standard deviations <16.1%. Furthermore, the method was applied successfully to analyse the pesticides in 15 pairs of organic and conventional vegetables. These results reflect the efficiency, reliability and robustness of the developed method.

Ratiometric fluorescence sensor for organophosphorus pesticide detection based on opposite responses of two fluorescence reagents to MnO2 nanosheets.

The detection of organophosphorus pesticides (OPs) has received considerable attention for their great harm to human beings. Herein, a novel ratiometric fluorescence biosensor was constructed for the determination of OPs by using Scopoletin (SC) and Amplex Red (AR) as probe pairs that have opposite responses to MnO2 nanosheets (MnO2 NS). MnO2 NS possess peroxidase-like catalytic activity, which could quench the fluorescence of SC as well as enhance the fluorescence of the non-fluorescent substance AR by oxidation. In the absence of OPs, acetylcholinesterase (AChE) hydrolyzed acetylcholine chloride (ATCh) into choline (TCh) and acetate. TCh led the decomposition of MnO2 NS to manganese ions (Mn2+), increasing signal of SC and decreasing signal of AR. In the presence of OPs, the activity of AChE was inhibited and the decomposition of MnO2 NS was hindered, therefore the fluorescence intensity of SC was weak and the fluorescence intensity of AR had an obvious increase. Moreover, under the optimal conditions, the ratio of fluorescence intensity response recorded on the AR/SC increases with increasing the concentration of DDVP. The method has wider linear range of 5.0 pg/mL ∼500 ng/mL with a detection limit of 1.6 pg/mL, which is superior to previously reported methods. This strategy has also been applied to a visual observation based on the color change of the solution under UV light.

Peptide Nanotube Encapsulated Enzyme Biosensor for Vapor Phase Detection of Malathion, an Organophosphorus Compound.

This study explores the use of a butyrylcholinesterase (BChE)-based, reversible reaction biosensor using screen-printed electrodes (SPEs) having a smaller working surface area than the single-use electrodes previously studied. Previous research demonstrated the prospective application of a single-use biosensor fabricated with an acetylcholinesterase (AChE) enzyme encapsulated in peptide nanotubes (PNTs) and enhanced with horseradish peroxidase (HRP) to detect organophosphorus compounds (OPCs) in aqueous and gas phases. In the current study, potential improvements to the biosensor are investigated. BChE-based biosensors were fabricated using PNTs, HRP, and Nafion in combination to increase the reactive surface area, enhance sensitivity, and maintain enzyme stability. Cyclic voltammetry (CV) was used along with the new modified sensor to measure malathion concentration in the gas phase. The results show that a BChE-based biosensor could reliably measure gas phase malathion concentrations between 6-25 ppbv by CV with the extent of inhibition linearly proportional to the malathion concentration (R2 = 0.941). This research demonstrated that fabricated BChE-based biosensors could be stored without cold storage requirement for up to six weeks with minimal performance degradation. Moreover, the sensor electrodes were each reused several times, and were still useable at the conclusion of the research. This research demonstrates the potential of fabricating a reusable, inexpensive biosensor that is capable of OPC detection with high sensitivity and a low detection limit without a long-term cold storage requirement.

Simultaneous determination of five organophosphorus pesticide residues in different food samples by solid-phase microextraction fibers coupled with high-performance liquid chromatography.

BACKGROUND: Excessive or improper use of organophosphorus pesticides (OPPs) may adversely affect human health through the food chain. In the present study, a simple, rapid and effective analytical method was successfully established and used for the determination of OPPs quinalphos and its analogs in different food samples. RESULTS: Under the optimized experimental conditions, five OPPs (quinalphos, triazophos, parathion, fenthion and chlorpyrifos-methyl) exhibit a good linearity within a range of 0.02 to 2.0 µg mL-1 . The detection limit range was 3.0 to 10.0 µg L-1 (signal-to-noise ratio = 3). The method was successfully used to detect and quantify the residues of quinalphos and its analogs in tomato, cabbage, barley and water samples; all spiked samples gave satisfactory recovery rates for the target analytes of between 82% and 98%, with a relative SD of 3.6% to 7.8%. CONCLUSION: The results obtained show that the proposed method is an accurate, rapid and reliable sample pre-treatment method with respect to giving a good enrichment factor and detection limit for determining quinalphos pesticide residues in different food samples. © 2019 Society of Chemical Industry.

Synthesized carbon nanodots for simultaneous extraction of personal care products and organophosphorus pesticides in wastewater samples prior to LC-MS/MS determination.

A simple, rapid and efficient solid-phase extraction method based on synthesized carbon nanodots was developed for the preconcentration and extraction of personal care products and organophosphorus pesticides in environmental matrices. Factorial (screening) and central composite designs were employed for the optimization of experimental conditions that could potentially influence the percentage recoveries of the target analytes. The experimental variables, including sample pH, mass of adsorbent, eluent volume and sample volume, were examined. Under the optimized conditions, the developed method was validated, and acceptable analytical results obtained showed good performance. The method accuracy carried out at two spiking levels (10 and 100 µg L-1) in different sample matrices ranged between 63 and 120%. The method precision based on relative standard deviation (% RSD) was < 10%. The linear range studied had a determination coefficient of (R2 > 0.995). The limits of detection (LOD) and limit of quantification (LOQ) established varied between 0.015-0.125 and 0.05-0.415 µg L-1 ,respectively. The ensuing method was applied successfully in the determination of the five multi-class organic compounds under study, in influent and effluent wastewater matrices, sampled from a municipal wastewater treatment plant located in Pretoria, South Africa.