Search

In this study, ultrasound-assisted dispersive magnetic solid phase extraction using toner powder (inexpensive and accessible magnetic sorbent) combined with flame atomic absorption spectrophotometry has been developed for the analysis of cobalt (II) in water and food samples. The influence of parameters (amount of toner powder, sample pH, the concentration of the complexing agent, eluent type and volume, and adsorption time) were studied as a function of the extraction recovery. The proposed method, which has been analytically characterized under its optimum operating conditions, allows the detection of cobalt (II) in the samples with method detection limits of 0.7 μg L−1. The method repeatability, expressed as the relative standard deviation (n = 10, Co2+= 50.0 μg L−1), was 3.1%, while the preconcentration factor was 50. Cobalt(II) was determined in water samples (tap water, river water, mineral water, seawater) and food samples (cabbage and cucumber) with good recoveries (96.0–104.0%) using the proposed method. [ABSTRACT FROM AUTHOR]

This research describes an easy, rapid, and inexpensive magnetic solid-phase extraction (MSPE) approach employing Fe3O4 magnetic nanoparticles modified with cetylpyridinium chloride (Fe3O4@CPC/MNPs) for extracting amoxicillin (AMX) and doxycycline (DOX) after derivatization with 4-chloroaniline as a color reagent. The azo-coupling of AMX and DOX with the color reagent in the alkaline medium caused yellow and yellow-orange azo dyes with maximum absorption wavelengths of 435 and 438 nm, respectively. The UV–Vis spectroscopy was utilized to determine the target analyte after the extraction procedure. Good linearities (R2 > 0.99) in the concentration ranges of 0.03–4.50 and 0.05–6.00 µg/mL were obtained for AMX and DOX, respectively. The experimental detection limits of AMX and DOX were obtained as 0.01 and 0.02 µg/mL, respectively. The developed approach was effectively applied to pre-concentrate and quantify AMX and DOX in environmental water and urine samples. [ABSTRACT FROM AUTHOR]

A simple, fast, and low-cost pre-concentration methodology based on the application of solid-phase extraction coupled to layered double hydroxides (LDHs) and capillary electrophoresis was developed for the determination of naproxen (NPX), diclofenac (DFC), and ibuprofen (IBP) in environmental sample waters. A systematic study of the LDH composition was designed, including the effects of interlayer anions (NO3−, Cl−, CO32−, BenO−, and SDS−) and the effect of molar ratio (Mg:Al). The optimal composition of MgAl/Cl−-LDH (Mg:Al; 1.5:1.0) was coupled to an SPE system: pH (neutral pH), LDH amount (15 mg), and extraction capacity ranged from 79.71 to 83.11% for the three anti-inflammatory non-steroidal agents analyzed. A recovery rate of up to 80.87% was obtained when 0.01 M chloride acid in methanol was used as the eluent and 50 mL of sample was used. Under optimal conditions, the linear range of the calibration curve ranges from 18.02 to 200 μg L−1, with limits of detection ranging from 6.03 to 18.02 μg L−1 for the three NSAIDs. The precision of the methodology was evaluated in terms of inter- and intra-day repeatability, with %RSD < 10% in all cases. The proposed method was applied to analyze environmental water samples (bottle, tap, cistern, well, and river water samples). The developed method is a robust technique capable of combining with other analytical methods to quantitatively determine anti-inflammatory non-steroidal agents. [ABSTRACT FROM AUTHOR]

In the presented study, an efficient and fast analytical method was developed for the determination of parathion ethyl as sarin simulant by gas chromatography–mass spectrometry (GC–MS). Dispersive solid phase extraction (DSPE) was performed to concentrate parathion ethyl from soil, plant and water samples. Reduced graphene oxide–iron (II, III) oxide (rGO-Fe3O4) nanocomposite was used as an adsorbent to collect the target analyte from the aqueous sample solutions. After the optimization of extraction/preconcentration parameters, optimum conditions for adsorbent amount, eluent type, mixing type/period, eluent volume and initial sample volume were determined as 15 mg, acetonitrile, vortex/30 s, 100 µL and 10 mL, respectively. Under the optimum conditions, analytical performance of the developed DSPE-GC–MS method was evaluated in terms of limit of detection (LOD), limit of quantitation (LOQ) and dynamic range. Dynamic range, LOD and LOQ values were figured out to be 0.94–235.15 µg/kg, 0.41 µg/kg and 1.36 µg/kg (mass based), respectively. Satisfactory percent recovery results (90.3–125% for soil, 93.5–108.7% for plant, 88.5–112.9% for tap water) were achieved for soil, plant and tap water samples which proved the accuracy and applicability of the developed method. It is predicted that the DSPE-GC–MS method can be accurately used for the detection of sarin in soil, plant and water samples taken from war territories. [ABSTRACT FROM AUTHOR]

For the first time, a highly permeable nanoporous carbon derived from melamine-based polybenzoxazine (NPC-PBZ-m) was used as the solid-phase extraction sorbent for trace analysis of atrazine (ATZ) herbicide in environmental water samples as a pre-treatment to enhance detection for high-performance liquid chromatography. Extraction performance was investigated using an agricultural field matrix-water sample. The parameters affecting the solid-phase extraction efficiency were carefully investigated. The optimisation conditions were determined as 200.0 mg of sorbent with an adsorption flow rate of 10.0 mL min−1, an elution flow rate of 1.0 mL min−1, and an elution volume of 3.0 mL. Moreover, it was not necessary to adjust the pH of the sample. Under these optimised extraction conditions, good linearity between 5.00 and 30.0 µg L−1 was achieved along with a limit of detection (LOD) of 1.25 µg L−1 and a limit of quantification (LOQ) of 3.79 µg L−1. Furthermore, the reusability of the NPC-PBZ-m column was found up to 8 cycles making it a new cost-effective material for herbicide enrichment. Finally, this developed method was successfully applied to analyse ATZ in water samples from rice fields, fish farms, and natural canal water, with 98–117% relative recoveries. These results indicate that NPC-PBZ-m with our proposed method is feasible and demonstrates its potential application as an effective adsorbent for herbicide enrichment. [ABSTRACT FROM AUTHOR]

This work describes the development of temperature-induced dispersive solid phase extraction (TI-DSPE) for the isolation and measurement of cobalt in food and water samples. The concentration of the preconcentrated cobalt ions was determined using flame atomic absorption spectrometry (FAAS). In TI-DSPE, the dispersion of the sorbent occurs by varying the temperature. The cobalt was complexed with 1-nitroso-2-naphthol and extracted with finely dispersed benzoic acid particles at 60 °C. The extraction efficiencies parameters were assessed and optimized, such as the mass of benzoic acid, dissolution temperature, solution pH, centrifugation conditions, and ionic strength. In the optimum conditions, the analytical curve was linear from 2.0 to 150.0 µg L−1, the limits of detection and quantification were 0.55 and 1.83 µg L−1 respectively, and the preconcentration factor was 50. Ten repeated measurements at 50.0 µg L−1 yielded a relative standard deviation (RSD) of 2.6% (n = 10). High extraction recoveries (96.5–102.5%) were obtained from the analysis of real samples. The validity of the developed procedure was confirmed by analyses of certified reference materials (QC-1187 and SPS-SW2). The results demonstrated that the developed method was simple, efficient, and cost-effective. [ABSTRACT FROM AUTHOR]

A simple and sensitive magnetic solid phase extraction (MSPE) method was developed for the separation-preconcentration and speciation of Cr in water samples. The system is based on the adsorption of Cr (VI)-ammonium pyrrolidinedithiocarbamate (APDC) complex on the activated charcoal@MoSe2@Fe3O4 composite. Total chromium has also been determined after the conversion of Cr (III) to Cr (VI) by oxidation with KMnO4. Cr (III) was determined as the difference between the total content of the Cr and Cr (VI). For quantitative recoveries, the effects of solution pH, adsorbent amount, volume of the sample, ligand volume, eluent type, and volume and effect of foreign ions were investigated. The limit of detection and limit of quantification for Cr was 0.36 ng mL−1 and 1.19 ng mL−1, respectively. The procedure was applied for the determination and speciation of chromium in water samples. [ABSTRACT FROM AUTHOR]

Nitrosamines and semi-volatile organic compounds (SVOCs) are carcinogenic contaminants in water and biological matrices. Conventional analytical methods often struggle to detect trace concentrations due to poor extraction efficacies. This study presents a novel, low-cost, in-syringe-assisted fast extraction cum cleanup technique coupled with GC-FID for monitoring four nitrosamines and two SVOCs in drinking water and human urine samples to measure the contamination and exposure levels. This extraction protocol combines a novel green in-syringe liquid–liquid extraction step using dimethyl carbonate as the green extraction solvent, coupled with a semi-automated solid-phase extraction cleanup process. Then, the final extractant is analyzed using gas chromatography-flame ionization detection (GC-FID) for monitoring. The method demonstrated excellent linearity (R2 > 0.998) between 1.5 and 500 ng mL⁻1 for all six target compounds. Detection limits ranged from 1.0 to 2.0 ng mL⁻1. Extraction recoveries were between 87 and 105% for both urine samples and water samples. Intra-day and inter-day precision were below 9% RSD. The blue applicability grade index evaluation scored 70.0, indicating good practical applicability. The developed analytical protocol offers a sensitive, accurate, low-cost, rapid, and environmentally friendly method for simultaneously quantifying multiple nitrosamines and SVOCs in environmental and human samples. Its performance characteristics and sustainability metrics suggest the potential for broad application in monitoring and exposure studies. [ABSTRACT FROM AUTHOR]

In this work, we test metal–organic frameworks (MOFs) as sorbents in the solid-phase extraction (SPE) technique to determine chemical warfare agents (CWAs) and their related compounds in water samples. During this study, we used 13 target compounds to test the selectivity of MOFs thoroughly. Three MOFs were used: MIL-100(Fe), ZIF-8(Zn), and UiO-66(Zr). The obtained materials were characterized using FT-IR/ATR, SEM, and XRD. CWA's and related compounds were analyzed using gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). The effect of the type of elution solvent and the amount of sorbent (MOFs) in the column on the efficiency of the conducted extraction were verified. The LOD ranged from 0.04 to 7.54 ng mL−1, and the linearity range for the analytes tested extended from 0.11/22.62 (depending on the compound) to 1000 ng mL−1. It was found that MOFs showed the most excellent selectivity to compounds having aromatic rings in their structure or a "spread" spatial structure. The best recoveries were obtained for DPAA, CAP, and malathion. Environmental water samples collected from the Baltic Sea were analyzed using an optimized procedure to verify the developed method's usefulness. [ABSTRACT FROM AUTHOR]

A straightforward and efficient dispersive micro solid-phase extraction was developed for extracting bicalutamide and flutamide as anti-cancers in real water and biological samples. A proper sorbent composite, including a metal-organic framework (CIM-80 (Al)), magnetic Nickel oxide nanoparticles, and Chitosan, was prepared. The ratio of the sorbent components was optimised using an optimal mixture design to increase the efficiency of the synthesised sorbent in the extraction of analytes. The optimum value of CIM-80 (Al), magnetic Nickel oxide nanoparticles, and Chitosan in the sorbent composition was 0.36, 0.22, and 0.42. The sorbent was characterised using XRD, FTIR, SEM, TEM, VSM, and BET analysis. Factors affecting the microextraction process were evaluated and optimised using a fractional factorial design and a central composite design. Under optimum conditions, the procedure was linear in the concentration range of 1.2–356.4 ng mL−1 and 0.89–348.7 ng mL−1 with a coefficient of determination of 0.9951 and 0.9947 for the determination of bicalutamide and flutamide, respectively. The detection limits and inter-day RSDs % for the bicalutamide and flutamide determination were lower than 0.35 ng mL−1 and 6.21%, respectively. Analysis of real water, drug-free urine, drug-free plasma, and post-drug urine samples indicated that the method has a high ability to analyse water and biological samples for the bicalutamide and flutamide determination. The method's effects on the environment for the bicalutamide and flutamide determination were evaluated using the Green Analytical Procedure Index and Analytical Eco-Scale. [ABSTRACT FROM AUTHOR]

A straightforward, fast and efficient analytical method was developed which utilizes a magnetic composite called three-dimensional graphene (3D-G@Fe3O4) as an adsorbent to recover nitrite ions (NO2−) from environmental water samples. The investigation into the synthesized adsorbent contained an examination of its morphology, chemical composition, structural attributes, and magnetic properties. This comprehensive analysis was conducted using various instrumental techniques, including Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Raman spectroscopy, X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH), and vibrating sample magnetometry (VSM). The adsorbent surface was activated by adding cetyltrimethylammonium bromide (CTAB) to the sample solution. To improve the selectivity and sensitivity of the method, nitrite ions were reacted with sulfanilic acid and chromotropic acid sequentially. An orange-red azo-dye complex was formed in the presence of nitrite ions with a clear absorbance peak at 514 nm. The effect of the main experimental parameters such as the pH of the sample solution, adsorbent dosage, and CTAB dosage was explored, and the optimization process was performed using a central composite design (CCD). The linear dynamic range (20–100 ng mL−1) was determined under optimal experimental circumstances, yielding a reasonable determination coefficient (R2, 0.9993), a detection limit of 5.12 ng mL−1, an enrichment factor of 167, and precision values of 1.0% intraday and 2.9% inter-day. The methodology successfully identified minute nitrite ions in environmental water samples with relative recoveries that varied between 96.05 and 101.6 ng mL−1. [ABSTRACT FROM AUTHOR]

A community engaged research (CER) approach was used to provide an exposure assessment of poly- and perfluorinated (PFAS) compounds in North Carolina residential drinking water. Working in concert with community partners, who acted as liaisons to local residents, samples were collected by North Carolina residents from three different locations along the Cape Fear River basin: upper, middle, and lower areas of the river. Residents collected either drinking water samples from their homes or recreational water samples from near their residence that were then submitted by the community partners for PFAS analysis. All samples were processed using weak anion exchange (WAX) solid phase extraction and analyzed using a non-targeted suspect screening approach as well as a quantitative approach that included a panel of 45 PFAS analytes, several of which are specific to chemical industries near the collection site locations. The non-targeted approach, which utilized a suspect screening list (obtained from EPA CompTox database) identified several PFAS compounds at a level two confidence rating (Schymanski scale); compounds identified included a fluorinated insecticide, a fluorinated herbicide, a PFAS used in polymer chemistry, and another that is used in battery production. Notably, at several locations, PFOA (39.8 ng/L) and PFOS (205.3 ng/L) were at levels that exceeded the mandatory EPA maximum contaminant level (MCL) of 4 ng/L. Additionally, several sites had detectable levels of PFAS that are unique to a local chemical manufacturer. These findings were communicated back to the community partners who then disseminated this information to the local residents to help empower and aid in making decisions for reducing their PFAS exposure. [ABSTRACT FROM AUTHOR]

Facile and sensitive methods for detecting neonicotinoids (NEOs) in aquatic environments are crucial because they are found in extremely low concentrations in complex matrices. Herein, nitrogen-based magnetic conjugated microporous polymers (Fe3O4@N-CMP) with quaternary ammonium groups were synthesized for efficient magnetic solid-phase extraction (MSPE) of NEOs from tap water, rainwater, and lake water. Fe3O4@N-CMP possessed a suitable specific surface area, extended π-conjugated system, and numerous cationic groups. These properties endow Fe3O4@N-CMP with superior extraction efficiency toward NEOs. The excellent adsorption capacity of Fe3O4@N-CMP toward NEOs was attributed to its π–π stacking, Lewis acid–base, and electrostatic interactions. The proposed MSPE-HPLC-DAD approach based on Fe3O4@N-CMP exhibited a wide linear range (0.1–200 µg/L), low detection limits (0.3–0.5 µg/L), satisfactory precision, and acceptable reproducibility under optimal conditions. In addition, the established method was effectively utilized for the analysis of NEOs in tap water, rainwater, and lake water. Excellent recoveries of NEOs at three spiked levels were in the range of 70.4 to 122.7%, with RSDs less than 10%. This study provides a reliable pretreatment method for monitoring NEOs in environmental water samples. [ABSTRACT FROM AUTHOR]

A novel approach employing activated nanodiamond combined with MIL-125 in micro solid-phase extraction has been successfully developed for the efficient extraction of cadmium and lead from food and water samples. Analytical parameters such as solution pH, adsorbent amount, sample volume, eluent concentration and volume, vortex time, and matrix effect to obtain the best recovery rates could be reached. The method's limits of detection were found to be 0.84 and 1.97 μg L−1 for Cd(II) and Pb(II). Its limits of quantification (LOQ) were found to be 2.81 and 6.57 μg L−1 for Cd(II) and Pb(II), respectively. Other performances that were found included preconcentration factors (PF) of 100 and 20 for Cd(II) and Pb(II), enhancement factors (EF) of 96 and 28 for Cd(II) and Pb(II), and relative standard deviation (RSD%) of 5.0 and 1.3 for Cd(II) and Pb(II), respectively. The method's validation was carried out using certified reference materials (SPS-WW2 wastewater and HR-1 Humber River sediment) ensuring its accuracy and reliability. The developed technique was successfully applied to determine the Cd(II) and Pb(II) contents in water and food samples. The optimized parameters and analytical characteristics demonstrate the method's efficiency in achieving low detection limits, high preconcentration factors, and reliable quantification. As a versatile tool for environmental and food safety analysis, this method contributes to the advancement of analytical techniques, ensuring accurate determination of trace metal concentrations in diverse sample matrices. [ABSTRACT FROM AUTHOR]

This study introduces a new in‐syringe homogeneous liquid‐phase microextraction method for the rapid on‐site extraction of chloroanilines from water samples. Extraction was performed using a plastic syringe, eliminating the use of any electrical power source. Di‐(2‐ethylhexyl) phosphoric acid (DEHPA) served as the extractant. The process initially involved dissolving DEHPA in an alkaline solution to obtain a homogeneous solution. Subsequently, the sodium salt of DEHPA was precipitated by salting‐out, and the resulting heterogeneous mixture was filtered using a syringe filter. The precipitate containing the analytes was then dissolved in methanol for analysis by high‐performance liquid chromatography. Under optimal conditions, extraction recovery for chloroanilines ranged from 26% to 71%. Method linearity was evaluated within a concentration range of 1.0–100 µg/L, resulting in coefficients of determination exceeding 0.9987 for all analytes. Method detection limits ranged from 0.28 to 0.41 µg/L. Intra and inter‐day precision values were below 9.5% and 10.8%, respectively. The developed method was applied to determine chloroanilines in real waters, yielding acceptable recoveries ranging from 80% to 109% for spiked tap, rain, and stream waters. Additionally, the method was successfully employed for on‐site extraction of target contaminants, demonstrating no statistically significant differences compared to laboratory results. [ABSTRACT FROM AUTHOR]

In this paper, a solid phase extraction procedure was developed for the simultaneous extraction of 22 multiclass high-risk pesticides, containing a variety of chemical groups (organophosphate, neonicotinoid, sulfonylurea, strobilurin, triazole, triazine, and acetanilide), from surface water samples. The target analytes extracted on the HLB SPE cartridge, and then eluted with acetonitrile with 5% (v/v) formic acid. The final sample solution was analysed by high-performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC–MS/MS) system. Under optimum conditions, good linearity was obtained for the target pesticides with correlation coefficient greater than 0.99. The limit of quantitation (LOQ) for the 22 pesticides was 0.1 ng/mL. The absolute recoveries of the pesticides from spiked water samples ranged from 70.0% to 121.5%. Relative standard deviations (RSD) for five replicate determinations were below 14.7%. The proposed method has been successfully applied to detect the presence of multiclass pesticides in environmental water samples. [ABSTRACT FROM AUTHOR]

Here, a simple/efficient analytical strategy based on dispersive solid phase extraction was developed using CoSn(OH)6 nanocubes for lead ions from environmental water samples by FAAS (flame atomic absorption spectrometry). CoSn(OH)6 was synthesized as an adsorbent using the co‐precipitation method and characterized. The characterization studies proved the cube‐shaped morphology and uniform size distribution. The optimal experimental conditions were found by optimization studies and, the limit of quantification (LOQ), limit of detection (LOD), linear dynamic range were recorded as 37.6 μg/L, 11.3 μg/L, and 40–600 μg/L, respectively. The enhancement factor of the presented method was calculated as 158.7‐folds compared to the LOD of the conventional FAAS system. Recovery experiments were performed to check the method's applicability/accuracy and the percent recovery results varied from 89.0 % to 112.9 %. According to these findings, the developed method was successfully applied for the quantitative determination of the target analyte in a seawater sample matrix. [ABSTRACT FROM AUTHOR]

• A series of novel fluorinated plant biomass adsorbents have been facilely synthesized. • The developed fluorinated cedar slag (FCS) exhibits excellent adsorption efficiency of PFCs. • The modified biomass material is suitable for the adsorption of PFCs from environmental water. • The FCS-SPE-HPLC-MS/MS approach can be applied for highly sensitive detection of PFCs. Perfluorinated compounds (PFCs) are toxic and widely present in the environment, and therefore effective adsorbents are required to remove PFCs from environmental water. In the present study, a new type of fluorinated biomass materials was synthesized via an ingenious fluorosilanization reaction. These adsorbents were applied for the adsorption of 13 typical PFCs, including perfluorocarboxylic acids (PFCAs) and perfluorosulfonic acids (PFSAs). By comparing their adsorption performance, Fluorinated cedar slag (FCS) was discovered to have the best absorption efficiency and enabled highly efficient enrichment of PFCs. The adsorption recovery of FCS with the investigated PFCs is greater than 90% under the optimal adsorption condition. Ascribed to the high affinity of F-F sorbent-sorbate interaction, FCS had good adsorption capacities of PFCs from aqueous solution, with the maximum adsorption capacity of 15.80 mg/g for PFOS and 10.71 mg/g for PFOA, respectively. Moreover, the adsorption time could be achieved in a short time (8 min). Using the FCS absorbent, an innovative FCS-solid phase extraction assisted with high performance liquid chromatography-electrospray-tandem mass spectrometry (FCS-SPE-HPLC-ESI-MS/MS) method was first developed to sensitively detect PFCs in the environmental water samples. The intra-day and inter-day recovery rates of the 13 compounds ranged from 90.7%-104.3%, with the RSD of 2.1%-4.7% (intra-day) and 2.5%-8.5% (inter-day), respectively. This research demonstrates the potential of the newly fluoro-functionalized plant biomass to adsorb PFCs from environmental water, with the advantages of high adsorption efficiencies, high anti-interference, easy operation and low economic cost. [Display omitted] [ABSTRACT FROM AUTHOR]

Multiwalled carbon nanotubes (MWCNTs) are well‐known adsorbents because of their high surface area, layered and hollow architecture, hydrophobicity, and multiple and easily accessible adsorption sites. In this study, MWCNTs were used for dispersive micro‐solid‐phase extraction of various metal chelates in environmental and food samples. Different parameters such as concentration of the chelating reagent, the sorbent dosage, the extraction time, the desorption time, and the strength of the eluent were suitably optimized. Under the optimum extraction conditions, the proposed method demonstrated a good linear working range for all the analytes, with correlation coefficients above 0.9915. The limit of detection ranged from 0.02 to 0.21 μg/L. The inter‐day and intra‐day relative standard deviations were less than 2.5 %. The proposed method was used for the determination of selected metals in tap water, drinking water, cucumber, and tomato samples. In the end, GAPI tool was used to evaluate the greenness of the method. [ABSTRACT FROM AUTHOR]

In this study, eight pharmaceuticals belonging to two classes, antihistaminic and antimigraine, were considered. Ultra‐performance liquid chromatography‐diode array detection was set up and gradient elution was used. The mobile phase was composed of acetonitrile and trifluoroacetic acid solution. Chromatographic separation was carried out with a run time of 9 min. The preconcentration of eight studied solutes was realized by micro solid‐phase extraction. Multiwalled carbon nanotubes, cetyltrimethylammonium bromide‐titanium dioxide nanotubes, and C‐18 bonded silica solid‐phase extraction (SPE) sorbents were evaluated and compared concerning recoveries. The results of the optimization of factors affecting the extraction efficiency including sample volume, the elution solvent type, and its volume are reported. For validation of the analytical procedure, specificity, linearity, precision, accuracy, limit of detection, and limit of quantification were evaluated. The developed method was successfully applied to the analysis of wastewater treatment samples. The extraction recoveries of pharmaceutical substances were above 81.23% for the three SPE sorbents. The extraction method was selective and the detection and quantification limits were between 0.004–0.02 and 0.01–0.06 μg/L, respectively. All the results indicated the potential application of the three studied SPE sorbents for the extraction of selected pharmaceuticals from wastewater. [ABSTRACT FROM AUTHOR]

Here, we deployed sol‐gel universal sorbent‐coated fabric phase sorptive extraction membranes in tandem with high‐performance liquid chromatography equipped with an ultraviolet detector (HPLC‐UV) for the analysis of 10 endocrine‐disrupting chemicals (EDCs). Due to the varying polarities of the studied compounds indicated by their octanol/water partition coefficient 'log Kow' (1.47–5.07), the extraction membrane was designed with different functionalities that are capable of simultaneous interaction with compounds of diverse natures including polar, non‐polar, and ionic species via sol‐gel sorbent coating technology. An isocratic mode of HPLC‐UV at 55:45% acetonitrile:water (v/v) on a reverse phase C18 Zorbax column (5 μm, 150 mm, 4.6 mm) was used for the separation and quantitation. Calibration curves were found linear between 25 and 2000 ppb for all compounds except cortisone in the range of 25–1000 ppb which provided an R2 value above 0.9940 in all cases. The intra‐day reproducibility and inter‐day reproducibility were found in the range of 1.2–12.8 and 0.2–14.1 (expressed as percent relative standard deviation), respectively. The validated method was finally deployed for the analysis of environmental water and milk samples with estradiol showing the highest concentrations among the studied compounds. [ABSTRACT FROM AUTHOR]

Fe3O4@nitrogen-doped carbon core-double shell nanotubes (Fe3O4@N-C C-DSNTs) were successfully synthesized and applied as a novel nanosorbent in ultrasonic assisted dispersive magnetic solid phase extraction (UA-DMSPE) of tribenuron-methyl, fenpyroximate, and iprodione. Subsequently, corona discharge ion mobility spectrometry (CD-IMS) was employed for the detection of the extracted analytes. Effective parameters on the extraction recovery percentage (ER%) were systematically investigated and optimized. Under optimal conditions, UA-DMSPE-CD-IMS demonstrated remarkable linearity in different ranges within 1.0 – 700 ng mL−1 with correlation coefficients exceeding 0.993, repeatability values below 6.9%, limits of detection ranging from 0.30 to 0.90 ng mL−1, high preconcentration factors (418 - 435), and ER% values (83 – 87%). The potential of the proposed method was further demonstrated by effectively determining the targeted pesticides in various environmental soil and water samples, exhibiting relative recoveries in the range 92.1 – 102%. [ABSTRACT FROM AUTHOR]

In analytical chemistry, the use of the simplest tool that provides the possibility of on-site measurement, low cost, and simple equipment has always been an area of interest for researchers. In recent years, the use of smartphones as an available tool can have these features. In this study, Bi2O3/ZnO/Pd adsorbent was used for preconcentration and measurement of Sudan IV color as one of the azo family colors in food and water samples, exploiting ultrasonic-assisted dispersive micro solid phase extraction (UA-d-µ-SPE) method along with a smartphone. The structure of this adsorbent was examined by XRD, SEM, and EDS analyses. Factors such as the amount of adsorbent (5.1 mg), sample solution pH (7.1), washing solvent volume (430.0 µL), and adsorption time (65 seconds) were optimized, utilizing central composite design (CCD) method. The type of washing solvent (methanol) and desorption time (45 seconds) were also optimized using the oneparameter-at-a-time method. In the best conditions, the limit of detection (LOD) was 5.58 ng mL-1, and the linear detection range (LDR) for this color was 20-1100 ng mL-1. The enrichment factor (EF) was also computed as 22.87. In addition, the relative standard deviation (RSD%) was acquired as 3.91 with n=5. [ABSTRACT FROM AUTHOR]

BACKGROUND: Phenolic endocrine‐disrupting chemicals (EDCs) are widespread and easily ingested through the food chain. They pose a serious threat to human health. Magnetic solid‐phase extraction (MSPE) is an effective sample pre‐treatment technology to determine traces of phenolic EDCs. RESULTS: Magnetic covalent organic framework (COF) (Fe3O4@COF) nanospheres were prepared and characterized. The efficient and selective extraction of phenolic EDCs relies on a large specific surface and the inherent porosity of COFs and hydrogen bonding, π–π, and hydrophobic interactions between COF shells and phenolic EDCs. Under optimal conditions, the proposed magnetic solid‐phase extraction‐high‐performance liquid chromatography–ultra violet (MSPE‐HPLC‐UV) based on the metallic covalent organic framework method for phenolic EDCs shows good linearities (0.002–6 μg mL−1), with R2 of 0.995 or higher, and low limits of detection (6–1.200 ng mL−1). CONCLUSION: Magnetic covalent organic frameworks (Fe3O4@COFs) with good MSPE performance for phenolic EDCs were synthesized by the solvothermal method. The magnetic covalent organic framework‐based MSPE‐HPLC‐UV method was applied successfully to determine phenolic EDCs in beverage and water samples with satisfactory recoveries (90.200%–123%) and relative standard deviations (2.100%–12.100%). © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In the present study, a homemade mixed-mode ion-exchange sorbent based on silica with embedded graphene microparticles is applied for the selective extraction of 2-aminobenzothiazole (NH2BT) followed by determination through liquid chromatography coupled to high-resolution mass spectrometry. The sorbent was evaluated for the solid-phase extraction of NH2BT from environmental water samples (river, effluent wastewater, and influent wastewater), and NH2BT was strongly retained through the selective cation-exchange interactions. Therefore, the inclusion of a clean-up step of 7 mL of methanol provided good selectivity for the extraction of NH2BT. The apparent recoveries obtained for environmental water samples ranged from 62 to 69% and the matrix effect from −1 to −14%. The sorbent was also evaluated in the clean-up step of the organic extract for the extraction of NH2BT from organic extracts of indoor dust samples (10 mL of ethyl acetate from pressurized liquid extraction) and fish (10 mL of acetonitrile from QuEChERS extraction). The organic extracts were acidified (adding a 0.1% of formic acid) to promote the cation-exchange interactions between the sorbent and the analyte. The apparent recoveries for fish samples ranged from 22 to 36% depending on the species. In the case of indoor dust samples, the recovery was 41%. It should be highlighted the low matrix effect encountered in such complex samples, with values ranging from −7 to 5% for fish and dust samples. Finally, various samples were analyzed. The concentration in river samples ranged from 31 to 136 ng/L; in effluent wastewater samples, from 55 to 191 ng/L; in influent wastewater samples, from 131 to 549 ng/L; in fish samples, from 14 to 57 ng/g dried weight; and in indoor dust samples, from

In recent years, the utilization of biomass materials for the removal and detection of water pollutants has garnered considerable attention. This study introduces, for the first time, the preparation of Fe3O4/persimmon leaf magnetic biomass composites. The magnetic composites were employed in a magnetic solid-phase extraction method, coupled with gas chromatography-electron capture detection (GC-ECD), for the analysis of four pesticides (trifluralin, triadimefon, permethrin, and fenvalerate) in environmental water samples. The innovative magnetic persimmon leaf composites were synthesized by in situ generation of Fe3O4 nanoparticles through coprecipitation and loaded onto persimmon leaves. These composites exhibit superparamagnetism with a saturation magnetization of 12.8 emu g−1, facilitating rapid phase separation using a magnetic field and reducing the extraction time to 10 min. Desorption can be achieved within 30 s by aspirating 20 times, eliminating the need for time-consuming and labor-intensive experimental steps like filtration and centrifugation. The specific surface area of the magnetic composite adsorbent increased from 1.3279 m2 g−1 for the original persimmon leaf to 5.4688 m2 g−1. The abundant hydroxyl and carboxyl groups on the composites provide ample adsorption sites, resulting in adsorption capacities ranging from 55.056 mg g−1 to 73.095 mg g−1 for the studied pesticides. The composites exhibited extraction recoveries ranging from 80% to 90% for the studied pesticides. Compared to certain previously reported MSPE methods, this approach achieves equivalent or higher extraction recoveries in a shorter operation time, demonstrating enhanced efficiency and convenience. Good linearity of the target analytes was obtained within the range of 0.75–1500 μg L−1, with a determination of coefficient (R2) greater than 0.999. These findings contribute to the use of magnetic persimmon leaf biomass materials as effective and environmentally friendly adsorbents for pollutant determination in water samples. [ABSTRACT FROM AUTHOR]

A novel bi-functionalized nanocomposite based on graphene oxide-alizarin red-S cross-linked-2-mercapto-N-(3-(triethoxysilyl) propyl) acetamide (ARS-MTPS@GO) was developed for the sequestration of cadmium Cd(II) ions from water. The nanocomposite fabrication was characterized through different physicochemical techniques (FTIR, XRD, SEM, TEM, Raman, and TGA). In addition to its hydrophilicity, high surface area, and ability to interact with the functionalized moieties, the ARS-MTPS@GO nanocomposite has improved Cd(II) adsorption. An optimization study was carried out on various analytical parameters that affect cadmium extraction, including the pH, contact time, and nanocomposite mass dosage. The maximum sorption capacity and percentage removal efficiency of Cd(II) ions reached 222.7 mg g−1 and 99.4 ± 3.7%, respectively, at pH = 6 within 30 minutes and the pseudo-second-order kinetic model best fits the sorption rate. Validation of the proposed method was evaluated for nine replicate measurements for recovery of Cd(II), showed favorable analysis precision, and the estimated detection limit was 0.18 ± 0.02 ng mL−1. Additionally, the reusability and stability of the nanocomposite and the effects of interfering cations and anions were investigated. Finally, the developed method was successfully applied for the selective extraction of Cd(II) from environmental water samples of different matrices, and the Cd(II) recoveries were 96.2–99.2%±2.3%. This study's findings prove the potential applicability of the novel nanocomposite for removing cadmium ions from different environmental waters. [ABSTRACT FROM AUTHOR]

In this study, a new sorbent was synthesized based on the in-situ growth of the combined ZIF-67 and ZIF-8 on the surface of MIL101. Finally, the adsorbent was made into a thin film with the help of polyvinylidene difluoride polymer and was used in the TFME technique for the simultaneous measurement of cadmium(II) and lead(II) metal ions in aqueous and cosmetic samples using flame atomic absorption spectroscopy. In order to achieve maximum efficiency and sensitivity, parameters affecting the extraction and desorption processes were optimized. Under the optimized condition, the linearity of the method, the limit of detections (LODs), the limit of quantifications (LOQs), the relative standard deviations (RSDs%), and enrichment factors (EFs) were equal with 0.2-150.0 µg l-1, 0.059-0.159 µg l-1, 0.197-0.530 µg l-1, 1.2 to 2.5% and 73-75, in water matrix, respectively. Then the optimal conditions for Pb and Cd were used in water and cosmetics samples by flame atomic absorption spectroscopy and acceptable results were obtained. [ABSTRACT FROM AUTHOR]

A modified Co3O4 nanocube-coated melamine-derived carbon sponge was synthesized and implemented for an in-syringe micro-solid-phase extraction approach as a promising sorbent. The introduced method combined with gas chromatography–flame ionization detection has been successfully developed for the determination of naphthalene, anthracene, and pyrene in environmental water samples. Significant adsorption and desorption parameters, including sorbent amount (19.0 mg), sample pH (7.4) and flow rate (233.0 µL min−1), salt concentration (20.0%), number of adsorption (4) and desorption (4) cycles, eluent volume (425.0 µL) and its flow rate (153.0 µL min−1), were optimized by the central composite design. Under the optimal conditions, the calibration curves were linear in the range of 3.0–500.0, 1.0–250.0, and 0.8–250.0 ng mL−1 for naphthalene, anthracene, and pyrene, respectively, along with acceptable intra- and inter-day precision (≤ 8.3%). The absolute recoveries were obtained in the range of 57.4–76.6%, while limits of detection were found between 0.2 and 0.8 ng mL−1. Eventually, the proposed method was successfully applied for the determination of the studied compounds in environmental and industrial water samples with satisfactory relative recoveries between 87.5 and 104.5%. The approach minimizes organic solvent consumption, sorbent amount, and sample solution volume, resulting in reasonable sensitivity and excellent reusability. This quantitative protocol is an efficient and satisfactory analytical procedure because of its high accuracy and precision. It proved to be highly cost-effective and reliable for screening purposes. [ABSTRACT FROM AUTHOR]

Background The increased use of cephalosporin antibiotics in the last few years as well as the detection of their residues in wastewater treatment plants and hospital wastewater poses a risk for infiltration of their residues into environmental water samples. Objective A simplified, sensitive, and convenient solid-phase extraction (SPE) procedure coupled with either HPLC or fast HPLC methods with diode array detection was developed and validated to screen the residues of six different cephalosporin antibiotics: cefoperazone, cefipime, ceftazedime, ceftriaxone, cefdinir, and cefotaxime, along with amoxicillin, levofloxacin, and ciprofloxacin in water samples. Methods An HPLC–diode array detector (HPLC–DAD) method and a fast HPLC method, based on a core-shell stationary phase, were developed for the fast screening of the antibiotic compounds. In addition, the SPE step was optimized to enable the extraction of the studied drugs with high accuracy of the recovered amounts of residues. Results The method sensitivity was enhanced by the coupling of SPE with HPLC–DAD and fast HPLC to achieve low LODs; from 0.2 to 3.8 ng/mL and from 0.65 to 12.2 ng/mL, respectively. The developed methods were augmented by LC–MS/MS determination for confirmation of identity and quantity of any positively identified sample. The method was applied to the analysis of water samples collected from a rural site. In Addition, an example application of cleaning validation of cefotaxime-contaminated stainless-steel surfaces was provided. Conclusion The method's simplicity and high sensitivity encourage its application in monitoring of antibiotic residues in different types of water samples such as environmental samples and samples from cleaning validation activities. Highlights HPLC–DAD and fast HPLC methods were developed for separation of nine different antibiotics. The combination with the SPE procedure achieved low detection limits; from 0.2 to 3.8 ng/mL for SPE–HPLC–DAD and from 0.65 to 12.2 ng/mL for SPE–fast HPLC. [ABSTRACT FROM AUTHOR]

In the separation and determination of trace amounts of drugs in aqueous samples, there is a major challenge in synthesizing highly efficient, cost‐effective, and easy‐to‐use adsorbents based on natural polymers, which are also biocompatible and biodegradable. In the proposed method, magnetite nanoparticles (Fe3O4) on chitosan (as the carrier) modified with β‐cyclodextrin (BCD) were used as a suitable adsorbent for the pre‐concentration and solid‐phase extraction of trace amounts of Amitriptyline HCl (hydrochloride). Ultraviolet spectrophotometer (λ = 236 nm) was the main instrument used for analyte detection and quantification. Moreover, X‐ray diffraction, Fourier transform infrared spectroscopy, Field Emission Scanning Electron Microscopy, and Energy‐Dispersive X‐ray were used for the identification and characterization of the structure and morphology of the adsorbent and to establish the formation of the synthesized magnetic nanosorbents, as well as to confirm the analyte binding to the adsorbent. Experimental variables affecting the extraction/pre‐concentration and determination of the analyte were investigated and optimized; pH of the sample solution, the amount of NaCl salt (in terms of ionic strength of the solution), the amount of adsorbent, temperature, adsorption time, and volume of the eluent (methanol) were the optimized parameters. Finally, the method was successfully applied for the determination of spiked Amitriptyline hydrochloride (HCl) in tap water and human urine samples. Also, High‐Performance Liquid Chromatography was performed on the aqueous samples to compare the proposed method with the USP (the United States Pharmacopeia) standard method of Amitriptyline HCl assay and after performing a t‐test (confidence level of 95%), no significant difference was observed between the two methods. High accuracy and precision (RSD = 3.91%), High analysis speed, few limitations, low expenses, pure extracted analyte, and low waste were the advantages of this method. This method was also compatible with many existing device methods. Under the optimized experimental conditions, the calibration graph was linear in the range of 0.183 to 50 mg.L−1 with a correlation coefficient of 0.996. RSD of the method was 3.91%, the limit of detection was 37.8 µg.L−1, the maximum sorption capacity of the adsorbent for Amitriptyline hydrochloride was 306.525 mg.g−1 and the preconcentration factor was 3.61. Eventually, the proposed method was compared to other methods that have been performed for the determination of Amitriptyline hydrochloride. [ABSTRACT FROM AUTHOR]

Magnetic dispersive micro solid-phase extraction as a proper and selective sample preparation was developed to extract and clean up three drugs, including Caffeine (CAF), Lidocaine (LID), and Chlorpromazine (CPZ), before determining by HPLC-DAD. Nickel-doped BiFeO3 was synthesised using the sol–gel method as a magnetic sorbent core and coated with tetraethyl orthosilicate (TEOS) to enhance the sorbent stability and the sorbent selectivity. In the extraction procedure, the sorbent was dispersed into acetonitrile as disperser solvent and sodium dodecyl sulphate (SDS) as a disperser agent before injecting into the sample solution to extract the analytes. Several influential factors in the method were evaluated using an experimental design strategy. Under the optimum conditions, the method displayed wide linearity in the concentration ranges of 20.8–365, 1.4–389, and 2.7–355 ng mL−1 to determine CAF, LID, and CPZ with a suitable R2 between 0.9963 and 0.9971, respectively. Intra-day and inter-day relative standard deviations were in the ranges of 3.5–3.8 and 3.9–4.3%. LODs and LOQs for the determination of CAF, LID, and CPZ were lower than 6.3 and 20.8 ng mL−1. The method is convenient for determining the analytes in real water and biological samples with RSD (n = 3) and recovery in the ranges of 3.0–4.3% and 87.5–96.9%, respectively. [ABSTRACT FROM AUTHOR]

In this work, is proposed an analytical method for the determination of nickel in natural water and sediment samples using solid-phase extraction with a mini-column of bamboo fibres modified with 5-Br-PADAP and determination by flame atomic absorption spectrometry. Applying the characterisation techniques of fresh bamboo fibre aimed to define the morphology of the fibre and its physical characteristics. Turning to the optimisation of the variables for the adsorptive process of nickel. The system allows the determination of nickel with a limit of detection (LOD) of 0.75 μg L−1 and a limit of quantitation (LOQ) of 2.50 μg L−1. The precision was expressed as a relative standard deviation (RSD) of 3.4 and 3.8% for a nickel concentration of 20.0 and 50.0 μg L−1 respectively. The value of 78.0 was determined as the value for the enrichment factor. The accuracy was confirmed with spike tests with recuperations varying from 91% to 106% and 93% to 104% for water and sediment samples, respectively, and by comparison with the certified sample. The procedure was applied for nickel determination in natural water and sediment samples. The achieved concentrations varied from 4.0–53.2 and 3.7–55.8 µg L−1 for water and sediment samples, respectively. [ABSTRACT FROM AUTHOR]

Aromatic compounds, such as 2,4-dinitrophenol (2,4-DNP), are one of the significant sources of environmental pollutants that are toxic compounds and have noxious effects on the environment and human health. In this project, 2-aminothiophenol magnetic nanoadsorbent (γ-Fe2O3@2-ATP) was synthesized and characterized. The prepared γ-Fe2O3@2-ATP was evaluated as a selective and efficient magnetic nanoadsorbent in the magnetic dispersive micro-solid phase extraction (MD–μ-SPE) method for the preconcentration and determination of trace amount of 2,4-DNP in the water samples spectrophotometrically. The significant variables, including the pH, amounts of sorbent, adsorption time, and desorption time, were optimized by experimental design method. Under optimized conditions, the linear range, limit of detection, and the relative standard deviation (%R.S.D) for the 2,4-DNP were 10–400, 2.73 ng mL−1, and 2.44% (n = 4), respectively. The method was successfully applied for the determination of 2,4-DNP in three different environmental water samples. It was validated via the analysis of the selected real samples by the high-performance liquid chromatography-ultraviolet detection method. Excellent recoveries for 2,4-DNP determination were obtained in spiked real samples. [ABSTRACT FROM AUTHOR]

Animal products are a major source of human exposure to steroids, this resulted in a critical request for applicable methods for the determination of these steroid hormones in pure form and in different matrices such as hen eggs, chicken liver and water. The aim was to develop a reliable LC-UV and LC-MS/MS for the determination of selected steroid hormones in edible samples, using SFE and LLE for sample preparation. LC-MS/MS method was validated for separation and quantification of selected steroid hormones; Ethinyl oestradiol, testosterone, 17 alpha methyltestosterone, and progesterone, using mobile phase of methanol and 0.1% Formic in ratio (70:30) at different m/z ratios. The developed method has satisfactory linearity and the spiking recoveries of the steroid hormones were between 90.25% and 99.45% with RSDs lower than 5%. The results demonstrated that the developed approach has high sensitivity and repeatability and can be helpful in the determination of steroid residues in complex food matrices. [ABSTRACT FROM AUTHOR]

In the present work, the herb (Poria cocos (Schw.) Wolf) residue, as an environmentally friendly and renewable biomass source, was converted into novel biochar. Biochar/sodium alginate mixed matrix membrane was fabricated. On this basis, a biochar/sodium alginate mixed matrix membrane‐based in‐syringe solid‐phase extraction was developed combined with ultra‐high performance liquid chromatography‐tandem mass spectrometry to determine nitroimidazoles in water samples. The factors including times of exaction, type, and volume of elution solvent, and sample solution pH were thoroughly optimized. Then the correlation coefficient was 0.9995–0.9997. The limit of detection of four analytes was between 0.006 and 0.014 ng/mL, and the recovery was between 79.02% and 99.1%. Consequently, the established method would provide a new perspective on monitoring nitroimidazoles in water samples. [ABSTRACT FROM AUTHOR]

Efficient and resilient techniques for handling samples are essential for detecting pharmaceutical compounds in the environment. This study explores a method for preserving water samples during transport before quantitative analysis. The study investigates the stability of 17α-ethynylestradiol (EE2), acetaminophen (ACM), oxytetracycline (OTC), sulfamethoxazole (SMX), and trimethoprim (TMP) after preconcentration within solid-phase extraction (SPE) cartridges. Through various experiments involving different holding times and storage temperatures, it was determined that four pharmaceutical compounds remained stable when stored for a month at 4°C and for six months when stored at −18°C in darkness. Storing these compounds in SPE cartridges at −18°C seemed effective in preserving them for extended periods. In addition, ACM, TMP, OTC, EE2, and SMX remained stable for three days at room temperature. These findings establish guidelines for appropriate storage and handling practices of pharmaceutical compounds preconcentrated from aqueous environmental samples using SPE. [ABSTRACT FROM AUTHOR]

To address sustainability issues, the green synthesis of nanomaterials has recently received considerable attention. This article addresses a novel and cost‐effective adsorbent for the extraction of eight phenyl‐N‐methylcarbamate insecticides from water samples. We first synthesized a magnetite/hydroxyapatite nanocomposite using snail shell powder via an environmental friendly approach. The morphology and physicochemical properties of magnetic hydroxyapatite were characterized by Fourier transform infrared spectroscopy, energy‐dispersive X‐ray spectroscopy, and scanning electron microscopy. Magnetic extraction parameters were optimized using a Doehlert matrix. Under optimum conditions, the magnetic extraction coupled with a LC–MS method shows good linearity with R2 ≥ 0.9982, suitable intra‐ and interday precision, and limits of detection and quantification in the range of 0.052–0.093 μg/L and 0.11–0.31 μg/L, respectively. Satisfactory relative recoveries of all carbamates were achieved from fortified water samples in the range of 93.89–101.01%. [ABSTRACT FROM AUTHOR]

Silica gel chemically functionalized with alizarin (Si-AZ) and 1-nitroso-2-naphthol (Si-NN) was synthesized and characterized by FT-IR, N2 adsorption-desorption, SEM, and elemental analysis. The two chelators show adequate sorption properties for Pb (II) and are hence used as SPE sorbents prior to their determination with ICP-MS. Both chelators showed high sorption efficiency for the Pb (II) ion at pH 8. Batch experiments demonstrate that the synthesized resins could remove more than 95% Pb (II) out of solutions containing 100 μg/mL of the ion. At optimum conditions, the maximum adsorption capacities for S-TDI-AZ and S-TDI-NN for Pb (II) were 9.56 and 9.43 mg/g, respectively. Method development was performed to investigate the applicability of the chelating resins as packing materials for SPE using model solutions and real groundwater samples. The method detection limits of SPE were 0.0025 and 0.0026 μg/L with high precision (R.S.D. < 3%). The recoveries of spiked Pb (II) with ground water were 104.70 and 102.62%. The proposed method was successfully applied to the determination of Pb (II) in the groundwater by ICP-MS. [ABSTRACT FROM AUTHOR]

Quantification of engineered nanomaterials in the environment has attracted researchers' interest recently because of their increased release to the environment. In this study, a recyclable and easily accessible magnetized coffee residue (MCR) is proposed for magnetic solid-phase extraction (MSPE) of zinc oxide nanoparticles (ZnO-NPs) from water samples. The MCR was synthesized using a simple one-step chemical coprecipitation method from coffee residue and was characterized by state-of-the-art techniques. Various parameters affecting the MSPE efficiency of ZnO-NPs were optimized and 8.5 pH, 75 mg adsorbent, 120 min extraction time, 10 mL sample volume, 4 mL of 0.001 M HCl as an eluting solvent, and 30 min elution time were identified as the optimum conditions. Under these conditions, the method showed excellent linearity (R2 = 0.995) and good sensitivity (detection limit, 0.12 mg L-1, and quantification limit, 0.4 mg L-1). Intra and inter-day percent standard deviations were 1.4 and 2.2%, respectively, for the analysis of 6 mg L-1 ZnO-NPs. The practical applicability of the method for the extraction of ZnO-NPs in environmental samples was evaluated, and recovery values in the range of 93.0-98.2% were obtained, confirming its successful performance. Generally, the technique is easy, economical, and eco-friendly that can be considered for the extraction of metal oxide nanoparticles. [ABSTRACT FROM AUTHOR]

The main aim of this work was to develop a suitable sorbent for the separation and determination of 226Ra through 133Ba (radio tracer) in water samples using fly ash sorbent. After the modification with KMnO4 the effects of pH, competing ions, the possibility of elution, and the effect of water volume were tested. As a suitable eluent 6 mol/L HCl was chosen, while the sorbent worked best at pH 6–8. The developed method is advantageous for minimizing the time required for separation, the volume of chemicals used, and the waste generated after separation. [ABSTRACT FROM AUTHOR]

This study introduced a new microextraction method named temperature‐induced dispersive solid‐phase extraction. The performance of the method was demonstrated with the determination of Sudan dyes in food and natural water samples. In this method, a low quantity of sorbent was added to the aqueous solution and the mixture was shaken manually for about one minute. Then, the solution was heated in an ultrasonic water bath, and the sorbent was dissolved. Subsequently, the solution was cooled down with ice water, and consequently, the solubility of the sorbent was reduced in the sample solution and became cloudy. The phase separation was accelerated by centrifugation. The upper liquid phase was picked up using a syringe, and the remainder was solved in methanol and introduced into the HPLC for analysis. Various parameters affecting the extraction yield were evaluated. Analytical parameters, including limits of detection (0.011–0.016 μg/L) and quantification (0.038–0.055 μg/L), relative standard deviations (2.3%–3.1%), and preconcentration factor (40) proved the high efficiency of the developed method for the analysis of Sudan dyes. The proposed method was used to measure Sudan dyes in water and food samples and showed good extraction recoveries (95.0%–103.5%). [ABSTRACT FROM AUTHOR]

A novel type of three-dimensional network structure, covalent organic frameworks (COFs) aerogel, was fabricated and applied to dispersive solid-phase extraction (dSPE) of quinolone antibiotics (QAs). Density functional theory (DFT) was applied to investigate the possible interaction mechanism and results confirmed that the strong adsorption affinity is attributed to the intralayer hydrogen bonds and π-π interaction. Furthermore, a sensitive analytical method based on COFs-aerogel for determining quinolone antibiotics residues in water and honey samples was developed and HPLC-MS/MS was used for sample detection and quantification. Under the optimal conditions, COFs-aerogel exhibited a wide linearity (0.1–500 ng∙L−1), low limits of detection (0.02–0.06 ng∙L−1), and good precision (RSD ˂ 10%) for selected QAs. A preliminary practical application of the developed method was proved by the efficient detection of quinolone antibiotics in water and food samples with good recoveries (68.2–104% and 64.0–100% for water and honey samples, respectively). Combining the experimental data with theoretical calculation, results illustrated that COFs-aerogel holds a great potential to capture contaminants and address environmental and food safety issues. [ABSTRACT FROM AUTHOR]

In this study, functionalized mesoporous silica was prepared and characterized as a stationary phase using various analytical and solid-state techniques, including a Fourier-transform infrared (FTIR) spectrometer, thermogravimetric analysis, and nitrogen sorption. The results confirmed the successful synthesis of the hybrid stationary phase. The potential of the prepared hybrid mesoporous silica as a solid-phase extraction (SPE) stationary phase for separating and enriching polycyclic aromatic hydrocarbons (PAHs) in both spiked water samples and real water samples was evaluated. The analysis involved extracting the PAHs from the water samples using solid-phase extraction and analyzing the extracts using a two-dimensional gas chromatograph coupled to a time-of-flight mass spectrometer (GC × GC-TOFMS). The synthesized sorbent exhibited outstanding performance in extracting PAHs from both spiked water samples and real water samples. In the spiked water samples, the recoveries of the PAHs ranged from 79.87% to 95.67%, with relative standard deviations (RSDs) ranging from 1.85% to 8.83%. The limits of detection (LOD) for the PAHs were in the range of 0.03 µg/L to 0.04 µg/L, while the limits of quantification (LOQ) ranged from 0.05 µg/L to 3.14 µg/L. Furthermore, all the calibration curves showed linearity, with correlation coefficients (r) above 0.98. Additionally, the results from real water samples indicated that the levels of individual PAH detected ranged from 0.57 to 12.31 µg/L with a total of 44.67 µg/L. These findings demonstrate the effectiveness of the hybrid mesoporous silica as a promising stationary phase for solid-phase extraction and sensitive detection of PAHs in water samples. [ABSTRACT FROM AUTHOR]

Selenium can either be essential or toxic depending on the concentration and oxidation state. In this study, the concentrations of inorganic selenium [Se(IV)] in water samples were determined in the presence of hexavalent selenium [Se(VI)} in water. Water samples were collected from ten different sampling sites in Blood and Mokolo Rivers in Limpopo Province, South Africa. A solid phase extraction (SPE) method with Dowex 1 × 2 resin (chloride form) as an adsorbent material was used to preconcentrate and separate Se(IV) selectively in the presence of Se(VI) in water samples. Concentrations of Se(IV) were quantified by inductively coupled plasma-mass spectrometry (ICP-MS) and ranged from 0.0411 to 0.820 µg/L and 0.135 to 2.79 µg/L in Blood and Mokolo Rivers, respectively. The presence of Se(IV) in water samples collected from Blood and Mokolo Rivers suggests that industrial and agricultural activities around these rivers have an impact on water quality. [ABSTRACT FROM AUTHOR]

Copyright of China Surfactant Detergent & Cosmetics (2097-2806) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present study describes the trace analysis of 23 fluorinated aromatic carboxylic acids based on the dispersive solid-phase extraction (dSPE) technique using UiO-66-NH2 MOF as efficient, recyclable sorbent, and GC–MS negative ionization mass spectrometry (NICI MS) as determination technique. All 23 fluorobenzoic acids (FBAs) were enriched, separated, and eluted in a shorter retention time; the derivatization was done by pentafluorobenzyl bromide (1% in acetone), in which the use of inorganic base K2CO3 was improved by triethylamine to increase the lifespan of the GC column. The performance of UiO-66-NH2 was evaluated by dSPE in Milli-Q water, artificial seawater, and tap water samples, and the impact of various parameters on the extraction efficiency was investigated by GC-NICI MS. The method was found to be precise, reproducible, and applicable to the seawater samples. In the linearity range, the regression value was found to be >0.98; LOD and LOQ were found to be in the range of 0.33–1.17 ng/mL and 1.23–3.33 ng/mL, respectively; and the value of the extraction efficiency was found to range between 98.45 and 104.39% for Milli-Q water samples, 69.13–105.48% for salt-rich seawater samples, and 92.56–103.50% for tap water samples with a maximum RSD value of 6.87% that confirms the applicability of the method to different water matrices. [ABSTRACT FROM AUTHOR]