Hollow fiber-based liquid phase microextraction (HF-LPME) for a highly sensitive HPLC determination of sulfonamides and their main metabolites

Thermo-Assisted Deep Eutectic Solvent Based on Dispersive Liquid-Liquid Microextraction for Preconcentration of Phthalate Esters in Water Samples and Determination by Gas Chromatography With Flame Ionization Detection

A thermo-assisted deep eutectic solvent (DES) based on dispersive liquid-liquid microextraction followed by gas chromatography with flame ionization detection was developed for the analysis of five phthalate esters in different water samples. In the procedure involved, a DES composed of lidocaine, an amphiphilic amine, and oleic acid, was mixed with the sample assisted by ultrasound, and phase separation was achieved with increasing temperature. The heating of the extraction system induced the change of acid-base properties of the DES components. Thus, the formation of microdroplets of DES in the sample was provided, and two phases were separated. The structure of the upper hydrophobic layer was characterized by Fourier-transform infrared spectroscopy. Also, the amount of water in the DES phase was analyzed by mass spectrometer and Karl Fischer titration. Some critical variables on the extraction yield were assessed. The proposed method achieved 1.2-1.3 and 4.1-4.3 µg/L for limits of detection and limits of quantification, respectively. The intra-day and inter-day percentage relative standard deviations (n = 5) were determined to be in the range of 4.2-6.2% and 5.1-7.2%, respectively. Ultimately, this method analyzed the five phthalate esters in different water samples with high recoveries.

Unraveling the effects of sulfamethoxazole on the composition of gut microbiota and immune responses in Stichopus variegatus

The aim of this work was to reveal the changes in gut microbiota composition and immune responses of sea cucumber (Stichopus variegatus) after being affected by different doses of sulfamethoxazole. In this study, the bacterial 16S rRNA of gut microbiota were analyzed by high-throughput sequencing, and the activities of immune enzymes [lysozyme (LZM), phenoloxidase (PO), alkaline phosphatase (AKP), and acid phosphatase (ACP)] in the gut of S. variegatus were determined. The results showed that the gut microbiota presented a lower richness in the antibiotic treatment groups compared with the control group, and there were significant differences among the dominant bacteria of different concentration treatments. At the genus level, the abundance of Escherichia, Exiguobacterium, Acinetobacter, Pseudomonas, and Thalassotalea were significantly decreased in the 3 mg/L treatment group, while Vibrio was significantly increased. Furthermore, the 6 mg/L treatment group had less effect on these intestinal dominant bacteria, especially Vibrio. The changes in relative abundance of Vibrio at the species level indicated that lower concentrations of sulfamethoxazole could enhance the enrichment of Vibrio mediterranei and Vibrio fortis in S. variegatus more than higher concentrations of sulfamethoxazole. Meanwhile, the 3 mg/L treatment group significantly increased the activities of PO, AKP, and ACP, and decreased the activity of LZM. These results suggested that lower doses of sulfamethoxazole have a greater effect on the gut microbiota composition and immune responses in S. variegatus and may increase the risk of host infection.

A New Trend and Future Perspectives of the Miniaturization of Conventional Extraction Methods for Elemental Analysis in Different Real Samples: A Review

Sample preparation is one of the viable procedures to be used before analysis to enhance sensitivity and reduce the matrix effect. The current review is mainly emphasized the latest outcome and applications of microextraction techniques based on the miniaturization of the classical conventional methods based on liquid-phase and solid-phase extraction for the quantitative elemental analysis in different real samples. The limitation of the conventional sample preparation methods (liquid and solid phase extraction) has been overcome by developing a new way of reducing size as compared with the conventional system through the miniaturization approach. Miniaturization of the sample preparation techniques has received extensive attention due to its extraction at microlevels, speedy, economical, eco-friendly, and high extraction capability. The growing demand for speedy, economically feasible, and environmentally sound analytical approaches is the main intention to upgrade the conventional procedures apply for sample preparation in environmental investigation. A growing trend of research has been perceived to quantify the trace for elemental analysis in different natures of real samples. This review also recapitulates the current futuristic scenarios for the green and economically viable procedure with special overemphasis and concentrates on eco-friendly miniaturized sample-preparation techniques such as liquid-phase microextraction (LPME) and solid-phase microextraction (SPME). This review also emphasizes the latest progress and applications of the LPME and SPME approach and their future perspective.

Hollow Fibre-Supported Liquid Membrane for the Determination of Sulfonamide Residues in Egg Samples

In this study, a three-phase hollow fibre-supported liquid membrane (HF-SLM) technique incorporated with high-performance liquid chromatography (HPLC) coupled with diode array detection (DAD) was developed for the extraction, clean-up, and determination of fifteen sulfonamide residues in chicken egg samples. The residues were extracted from the 5 mL sample solution of pH 2.5 into a thin layer of organic phase (1-octanol with 10% TOPO) immobilised in hollow fibre pores and then back-extracted into approximately 6 μL of aqueous phase (pH 13) located in the lumen of the hollow fibre. After extraction, 6 μL of the acceptor phase was injected into an HPLC instrument for subsequent analysis. Under optimum conditions, the limit of detection (LOD) and limit of quantification (LOQ) values ranged from 0.8–7.9 μg·kg−1 and from 2.4–21.0 μg·kg−1, respectively, linearity in the range of 5 1 000 μg·kg−1, and intra- and inter-day precision (%RSD) values at three concentration levels (50, 100, and 500 μg·L−1) ranged from 6.2–15.7%, 7.3–15.0%, and 7.3–14.6%; and 6.4–17.4%, 4.3–16.2%, and 8.3–16.5%, respectively, were obtained. The accuracy of the method, expressed as percentage recovery, was in the range of 71.0–98.7%, with corresponding %RSD (n = 6) values ranging from 1.9–9.9% being obtained. The developed method provided enrichment factors in the range of 17.1 to 541.4. The applicability of the proposed method was also evaluated by analysing egg samples, which were randomly collected from local supermarkets located in Gauteng Province, South Africa. The results obtained revealed that the developed method has the potential to be used as an alternative method for the determination of sulfonamide residues in egg and related complex samples.

A Green HPLC Method for Determination of Nine Sulfonamides in Milk and Beef, and Its Greenness Assessment with Analytical Eco-Scale and Greenness Profile

BACKGROUND

Sulfonamides have been widely used in the prevention and clinical treatment of bacterial diseases in livestock and poultry. The use of sulfonamides increases the risk of veterinary drug residues in animal derived foods. The traditional reversed phase liquid chromatography methods for sulfonamides residues detection in animal derived foods have the problem of high consumption of organic solvents.

OBJECTIVE

The aim of this study was to establish a green high-performance liquid chromatography method for the detection of sulfonamides residues in different animal-origin foods.

METHOD

The sample extraction solutions were purified by the Agela Cleanert PEP-2 cartridge and analyzed by the high-performance liquid chromatography method using ethanol as the green alternative solvent.

RESULTS

The proposed method was validated in terms of linear range (20-1000 μg/kg), limit of detection (3.0-12.3 μg/kg), limit of quantitation (10-43 μg/kg), accuracy (80.7-101.3%), and repeatability and reproducibility (RSD <5.9% and RSD <8.5% respectively).

CONCLUSIONS

The proposed method is an environmentally friendly, sensitive and reliable high-performance liquid chromatography method for simultaneous determination of sulfonamide residues in animal-origin foods.

HIGHLIGHTS

In this work, we firstly developed a green high-performance liquid chromatography method for simultaneous determination of the residues of nine sulfonamides in milk and beef with ethanol as the green alternative solvent.

A selective and efficient microfluidic method-based liquid phase microextraction for the determination of sulfonamides in urine samples

Liquid phase microextraction (LPME) into a microfluidic has undergone great advances focused on downscaled and miniaturized devices. In this work, a microfluidic device was developed for the extraction of sulfonamides in order to accelerate the mass transfer and passive diffusion of the analytes from the donor phase to the acceptor phase. The subsequent analysis was carried out by high performance liquid chromatography with UV-DAD (HPLC-DAD). Several parameters affecting the extraction efficiency of the method such as the supported liquid membrane, composition of donor and acceptor phase and flow rate were investigated and optimized. Tributyl phosphate was found to be a good supported liquid membrane which confers not only great affinity for analytes but also long-term stability, allowing more than 20 consecutive extractions without carry over effect. Under optimum conditions, extraction efficiencies were over 96 % for all sulfonamides after 10 minutes extraction and only 10 µL of sample was required. Relative standard deviation was between 3-5 % for all compounds. Method detection limits were 45, 57, 54 and 33 ng mL^-1 for sulfadiazine (SDI), sulfamerazine (SMR), sulfamethazine (SMT) and sulfamethoxazole (SMX), respectively. Quantitation limits were 0.15, 0.19, 0.18 and 0.11 µg mL^-1 for SDI, SMR, SMT SMX, respectively. The proposed microfluidic device was successfully applied for the determination of sulfonamides in urine samples with extraction efficiencies within the range of 86-106 %. The proposed method improves the procedures proposed to date for the determination of sulfonamides in terms of efficiency, reduction of the sample volume and extraction time.

Application of Hollow Fibre-Liquid Phase Microextraction Technique for Isolation and Pre-Concentration of Pharmaceuticals in Water

In this article, a comprehensive review of applications of the hollow fibre-liquid phase microextraction (HF-LPME) for the isolation and pre-concentration of pharmaceuticals in water samples is presented. HF-LPME is simple, affordable, selective, and sensitive with high enrichment factors of up to 27,000-fold reported for pharmaceutical analysis. Both configurations (two- and three-phase extraction systems) of HF-LPME have been applied in the extraction of pharmaceuticals from water, with the three-phase system being more prominent. When compared to most common sample preparation techniques such as solid phase extraction, HF-LPME is a greener analytical chemistry process due to reduced solvent consumption, miniaturization, and the ability to automate. However, the automation comes at an added cost related to instrumental set-up, but a reduced cost is associated with lower reagent consumption as well as shortened overall workload and time. Currently, many researchers are investigating ionic liquids and deep eutectic solvents as environmentally friendly chemicals that could lead to full classification of HF-LPME as a green analytical procedure.

Metal-organic framework MIL101 (Cr)-NH2 functionalized magnetic graphene oxide for ultrasonic-assisted magnetic solid phase extraction of neonicotinoid insecticides from fruit and water samples

In this work, a magnetic nanocomposite composed of graphene oxide (GO), silica-coated cobalt ferrite (CoFe2O4@SiO2) nanoparticles and amino-functionalized metal-organic framework (MIL 101 (Cr)-NH2) was fabricated and employed for ultrasonic-assisted magnetic solid phase extraction (UA-MSPE) of neonicotinoid insecticides. Various techniques such as Fourier transform infrared (FT-IR) spectrometry, vibrating sample magnetometry (VSM), energy-dispersive X-ray spectroscopy (EDS) and field emission scanning electron microscope (FE-SEM) measurements were executed to investigate features and morphology of the adsorbent. The magnetic graphene oxide functionalized MIL-101 (Cr)-NH2 (MGO/MIL) combines the advantages of magnetic GO and MIL 101(Cr)-NH2 such as excellent thermal and chemical stability, high surface area, accessible coordinative unsaturated sites, sufficient stability in aqueous solutions and rapid and easy separation from the solution. Some of the important extraction factors such as type and volume of desorption solvent, desorption time, salt concentration, adsorbent amount, pH and extraction time were investigated in detail to achieve high MSPE recovery. In optimal condition, the limits of detection (LODs) for Acetamiprid and Imidacloprid were achieved 0.022 and 0.019 ng mL-1, respectively. Good determination coefficients (R2 more than 0.9990) with satisfactory linearity in the range of 0.064-3500 ng mL-1 were found for this method. The relative standard deviations for intra- and inter-day analyses were in the range of 3.93-4.56% and 7.80-8.50%, respectively. The method was successfully used for analyzing of neonicotinoid insecticides in water and fruit samples and acceptable recoveries from 82.13% to 102.27% were obtained. The results indicated that the nanocomposite is feasible for the adsorption of trace amounts of the target analytes from the fruit and water samples.

Ionic Liquid-based Hollow Fiber Liquid–Liquid–Liquid Microextraction Combined with Capillary Electrophoresis for the Determination of Sulfonamides in Aquaculture Waters

Ionic liquid-based hollow-fiber liquid–liquid–liquid microextraction (IL-HF-LLLME) coupled to capillary electrophoresis (CE) has been developed for the determination of six sulfonamides (SAs) in aquaculture waters. A series of extraction parameters was optimized to enhance the extraction efficiency, which included type and pore size of hollow fiber, type and composition of extraction solvent, pH value of donor phase, the concentration of acceptor phase and the mass ratio of donor phase to acceptor phase along with extraction temperature and time. Under optimal conditions, the IL-HF-LLLME-CE method provided a wide liner range for six SAs from 2 to 1,000 μg L−1 (r2 ≥ 0.9995), the limits of the detection from 0.25 to 0.48 and the enrichment factors from 122 to 230, respectively. Relative standard deviations for intra- and interday precision were 1.4–5.3% and 1.8–7.5% (n = 5), respectively. The proposed method was successfully applied for the determination of trace-level SAs in seven real-world aquaculture water samples with good recoveries (80.4–100.7%). Also, sulfamerazine and sulfamethoxazole were detected at the level of 0.52–1.60 μg L−1 in two water samples. Due to its good sensitivity, simple operation, short analysis time and eco-friendliness, the developed method has a great application potential in analysis of trace SA residues in aquaculture waters.

Identification of antibiotics in wastewater: current state of extraction protocol and future perspectives

The release and occurrence of antibiotics in the aquatic environment has generated increased attention in the past few decades. The residual antibiotic in wastewater is important in the selection for antimicrobial resistance among microorganisms and the possibility of forming toxic derivatives. This review presents an assessment of the advancement in methods for extraction of antibiotics with solid phase extraction and liquid-liquid extraction methods applied in different aquatic environmental media. These advanced methods do enhance specificity, and also exhibit high accuracy and recovery. The aim of this review is to assess the pros and cons of the methods of extraction towards identification of quinolones and sulphonamides as examples of relevant antibiotics in wastewater. The challenges associated with the improvements are also examined with a view of providing potential perspectives for better extraction and identification protocols in the near future. From the context of this review, magnetic molecular imprinted polymer is superior over the remaining extraction methods (with the availability of commercial templates and monomers), is based on less cumbersome extraction procedures, uses less solvent and has the advantage of its reusable magnetic phase.

A sensitive method for the determination of Sulfonamides in seawater samples by Solid Phase Extraction and UV-Visible spectrophotometry

The authors have developed a sensitive spectrophotometric method for determination of sulfonamide derivatives such as sulfanilamide (SAA), sulfadiazine (SDZ), sulfacetamide (SCT) sulfamethoxazole (SMX), sulfamerazine (SMR), sulfadimethoxine (SDX), sulfamethiazole (SMT) and Sulfathiazole (STZ). This method is based on the Bratton-Marshall reaction, which involves the diazotization of sulfonamides with sodium nitrite under acidic conditions, followed by coupling with N-(1-naphtyl) ethylenediamine dihydrochloride (NED) to form a pink colored compound. Therefore, the Bratton-Marshall method was modified by optimizing the reaction conditions, which allows us to determine a low concentration range of sulfonamides compared to the reported methods. The limits of detection and quantification obtained were 0.019-0.05 and 0.06-0.16μgmL^-1, respectively. In comparison with other reported methods using different coupling agents, the proposed method was found to be the most simple and sensitive for sulfonamides determination. In this paper, the modified method was successfully employed for the determination of sulfonamides in drinking water, seawater and pharmaceutical and veterinary formulations. The purpose of this work is to optimize and develop a simple method for extraction and concentration of sulfonamides present as residues in seawater and their quantification with the recommended spectrophotometric method. Solid phase extraction (SPE) of sulfonamides from seawater samples was evaluated using Oasis HLB cartridges (3mL, 540mg). The recovery efficiency was investigated in the sulfonamides concentration range comprised between 0.19 and 126ngmL^-1. The ease of use of this extraction method makes it very useful for routine laboratory work.

Estimation of the toxicity of sulfadiazine to Daphnia magna using negligible depletion hollow-fiber liquid-phase microextraction independent of ambient pH

The toxicity of ionizable organic compounds to organisms depends on the pH, which therefore affects risk assessments of these compounds. However, there is not a direct chemical method to predict the toxicity of ionizable organic compounds. To determine whether hollow-fiber liquid-phase microextraction (HF-LPME) is applicable for this purpose, a three-phase HF-LPME was used to measure sulfadiazine and estimate its toxicity to Daphnia magna in solutions of different pH. The result indicated that the sulfadiazine concentrations measured by HF-LPME decreased with increasing pH, which is consistent with the decreased toxicity. The concentration immobilize 50% of the daphnids (EC50) in 48 h calculated from nominal concentrations increased from 11.93 to 273.5 mg L⁻¹ as the pH increased from 6.0 to 8.5, and the coefficient of variation (CV) of the EC50 values reached 104.6%. When calculated from the concentrations measured by HF-LPME (pH 12 acceptor phase), the EC50 ranged from 223.4 to 394.6 mg L⁻¹, and the CV decreased to 27.60%, suggesting that the concentrations measured by HF-LPME can be used to estimate the toxicity of sulfadiazine irrespective of the solution pH.

Determination of Carotenoids in Egg Yolk by High Performance Liquid Chromatography with Vortex-Assisted Hollow Fiber Liquid-Phase Microextraction using Mixed Extraction Solvent

A vortex-assisted hollow fiber liquid-phase microextraction method using a mixed solvent as the extraction solvent followed by high performance liquid chromatography diode-array detection was developed for the extraction and determination of two carotenoids including lutein and β-carotene from egg yolk. The method is based on the microextraction of carotenoids from sample solution into extracting agent (20 μL), which is located in the lumen of hollow fiber followed by vortex-mixing. The mixed solvent (1-octanol+1-undecanol, 6:4, v:v) was employed as extracting agent for it has suitable viscosity and compatible with carotenoids via hollow fiber. Vortex-mixing was utilized to provide effective and mild mixing of sample solution and increase the contact between analytes and boundary layers of the hollow fiber. Parameters influencing recoveries were investigated and optimized. Under the optimum conditions, the linear range of lutein and β-carotene were from 50 to 1,000 ng mL^-1 The correlation coefficients of the calibration curves were >0.9982, relative standard deviations (n = 5) were between 2.23% and 3.51% and the limits of detection were 0.038 and 0.045 μg mL^-1 for lutein and β-carotene, respectively. The proposed method was successfully applied to the extraction and determination of caroteonids in egg yolk with the satisfactory relative recoveries (90.2-101.8%).

Headspace Microextraction of Sulfonamides from Honey by Hollow Fibers Coupled with Ultrasonic Nebulization

A new method for the rapid simultaneous determination of five sulfonamides in honey was developed using ultrasonic nebulization-assisted extraction coupled with hollow fiber liquid-liquid-liquid microextraction prior to liquid chromatography. In the present method, the sample solution was nebulized by ultrasonication. Sulfonamides in the aerosol particles were extracted by 1-octanol impregnated in the pores of a hollow fiber and further into the acceptor phase (acid solution, pH 2.0) contained in the lumen of the hollow fiber. Several experimental parameters that affect the extraction efficiency were optimized. The present method provides good recoveries (88.9-114.2%) and acceptable precision (<10.7%), indicating the effective extraction. The detection limits were 4.6-6.8 μg/kg, lower than the maximum residue limits of sulfonamides in honeys. Compared to the traditional extraction methods, the present method requires less organic solvent and operation time, demonstrating excellent cleanup ability and good enrichment efficiency.

Microwave-assisted liquid-liquid microextraction based on solidification of ionic liquid for the determination of sulfonamides in environmental water samples

An easy, quick, and green method, microwave-assisted liquid-liquid microextraction based on solidification of ionic liquid, was first developed and applied to the extraction of sulfonamides in environmental water samples. 1-Ethy-3-methylimidazolium hexafluorophosphate, which is a solid-state ionic liquid at room temperature, was used as extraction solvent in the present method. After microwave irradiation for 90 s, the solid-state ionic liquid was melted into liquid phase and used to finish the extraction of the analytes. The ionic liquid and sample matrix can be separated by freezing and centrifuging. Several experimental parameters, including amount of extraction solvent, microwave power and irradiation time, pH of sample solution, and ionic strength, were investigated and optimized. Under the optimum experimental conditions, good linearity was observed in the range of 2.00-400.00 μg/L with the correlation coefficients ranging from 0.9995 to 0.9999. The limits of detection for sulfathiazole, sulfachlorpyridazine, sulfamethoxazole, and sulfaphenazole were 0.39, 0.33, 0.62, and 0.85 μg/L, respectively. When the present method was applied to the analysis of environmental water samples, the recoveries of the analytes ranged from 75.09 to 115.78% and relative standard deviations were lower than 11.89%.

Preparation of molecularly imprinted polymers based on magnetic carbon nanotubes for determination of sulfamethoxazole in food samples

An efficient approach was developed to synthesize the imprinted magnetic carbon nanotubes nanocomposite and apply for sulfamethoxazole enrichment from milk and honey samples.

A sensitive emulsification liquid phase microextraction coupled with on-line phase separation followed by HPLC for trace determination of sulfonamides in water samples

For the first time, ion-pair based emulsification liquid phase microextraction coupled with a novel approach for phase separation followed by high performace liquid chromatgraphy (HPLC) was utilized for trace determination of sulfonamides in water samples. After the formation of ion-pair complex with a cationic surfactant, sulfonamides were extracted into the drops of dispersed organic extracting solvent. Then, the cloudy solution was passed through an in-line filter located in a suitable holder and was separated based on emulsion filtration. By changing the HPLC valve position, the filter was laid in the mobile phase path, and the extraction phase was eluted by the mobile phase and introduced into the separation column for analysis. The effects of important parameters, such as type of extraction solvent, type of ion-pair agent and its concentration, pH of sample solution, ionic strength, and volume of extraction phase, on the extraction efficiency, were investigated and optimized. Under optimal conditions, the linear range, limits of detection, and precision (relative standard deviations) were 0.3-100, 0.1-0.3 μg L(-1), and 4.7-5.8%, respectively. Preconcentration factors (PFs) for the compounds studied were obtained in the range of 268-664. These PFs correspond to extraction recoveries in the range of 41-97%. The sample throughput of the method was 3 samples per hour, regarding 20 min analysis time for a single procedure. Finally, the method was successfully applied to determine the selected sulfonamides in some water samples.