Enhancement for trace analysis of sulfonamide antibiotics in water matrices using bar adsorptive microextraction (BAμE)

Rapid determination of sulfamethoxazole and trimethoprim illegally added to health products using excitation-emission matrix fluorescence coupled with the second-order calibration method

In this work, a simple and fast analytical method based on a self-weighted alternating trilinear decomposition (SWATLD) algorithm coupled with excitation-emission matrix (EEM) fluorescence was developed for the simultaneous determination of sulfamethoxazole (SMZ) and trimethoprim (TMP) illegally added to health products. With the second-order advantage, the proposed method obtained satisfactory results in the presence of peak overlap and unknown interferences. The analysis time for a single sample is only 0.8 minutes. The average spiked recoveries of SMZ and TMP in three health product spiked samples were in the range of 91.0-106.2% and 86.8-107.8%, respectively. The relative standard deviations (RSDs) were lower than 8.6%. In addition, verification parameters including sensitivity (SEN), selectivity (SEL), the limit of detection (LOD), the limit of quantification (LOQ), intra-day precision, and inter-day precision were calculated, and the results show that the proposed method is feasible. The quantitative results of the proposed method were further confirmed by the LC-MS/MS method, which proved that the proposed method was efficient and green for drug-abuse monitoring of SMZ and TMP in health products.

Sample preparation optimization by central composite design for multi class determination of 172 emerging contaminants in wastewaters and tap water using liquid chromatography high-resolution mass spectrometry

Multi-residue analysis is highly desirable for water quality control. To this end, a comprehensive workflow for the quantitative analysis of 172 anthropogenic organic compounds belonging to emerging contaminants (pharmaceuticals and personal care products, illicit drugs, organophosphate flame retardants and perfluoroalkyl substances) has been developed for application to wastewater and tap water, based on solid phase extraction (SPE) and Orbitrap high resolution mass spectrometry (HRMS). Due to the large number of analytes with various physicochemical characteristics that should be efficiently extracted, the response surface methodology (RSM) employing a central composite design (CCD) and desirability function (DF) approach was exploited to optimize the sample preparation process, instead of the conventional single-factor analysis. The factors included in the design of experiments (DoE) were sample pH, eluent solvents composition and volume. Statistical analysis (ANOVA) proved the adequacy of the proposed model (2- factor interaction) as p-value < 0.05 followed by different diagnostic tests confirmed the good fitting. The best values to acquire DF close to 1 were pH 3.5, methanol/ethyl acetate ratio 87:13 and eluent volume 6 mL. The streamlined method was validated in terms of accuracy, linearity, method limits, reproducibility, and matrix effect. The proposed workflow combines sensitivity and robustness, with recoveries over 70%, method quantification limits <1 ng/L, and relative standard deviations <20% for most of the compounds. Slight matrix effect (ME) was observed for most of PPCPs, IDs and PFAs, in contrast with most of the OPFRs, for which strong ME was calculated. Method applicability was tested over wastewater collected from a municipal wastewater treatment plant in Thessaloniki (Greece), revealing the presence of 69 and 40 compounds in influents and effluents, respectively, at varying concentrations.

Application of Bar Adsorptive Microextraction for the Determination of Levels of Tricyclic Antidepressants in Urine Samples

This work entailed the development, optimization, validation, and application of a novel analytical approach, using the bar adsorptive microextraction technique (BAμE), for the determination of the six most common tricyclic antidepressants (TCAs; amitriptyline, mianserin, trimipramine, imipramine, mirtazapine and dosulepin) in urine matrices. To achieve this goal, we employed, for the first time, new generation microextraction devices coated with convenient sorbent phases, polymers and novel activated carbons prepared from biomaterial waste, in combination with large-volume-injection gas chromatography-mass spectrometry operating in selected-ion monitoring mode (LVI-GC-MS(SIM)). Preliminary assays on sorbent coatings, showed that the polymeric phases present a much more effective performance, as the tested biosorbents exhibited low efficiency for application in microextraction techniques. By using BAμE coated with C18 polymer, under optimized experimental conditions, the detection limits achieved for the six TCAs ranged from 0.2 to 1.6 μg L-1 and, weighted linear regressions resulted in remarkable linearity (r2 > 0.9960) between 10.0 and 1000.0 μg L-1. The developed analytical methodology (BAμE(C18)/LVI-GC-MS(SIM)) provided suitable matrix effects (90.2-112.9%, RSD ≤ 13.9%), high recovery yields (92.3-111.5%, RSD ≤ 12.3%) and a remarkable overall process efficiency (ranging from 84.9% to 124.3%, RSD ≤ 13.9%). The developed and validated methodology was successfully applied for screening the six TCAs in real urine matrices. The proposed analytical methodology proved to be an eco-user-friendly approach to monitor trace levels of TCAs in complex urine matrices and an outstanding analytical alternative in comparison with other microextraction-based techniques.

Bar adsorptive microextraction device coated with polyimide microsphere assembled by nanosheets combined with thermal desorption-gas chromatography for trace analysis of nitroaromatic explosives in environmental waters

Polyimide (PI) microspheres assembled by nanosheets were used for bar adsorptive microextraction (BAμE) for the first time. The PI microsphere possessed self-organized hierarchical nanostructure, large specific surface area (170 m²/g) and good thermostability (up to 400 °C). The BAμE device was prepared by adhering the PI microspheres on a quartz bar with Kapton double sided tape. Trace nitroaromatic explosives in environmental waters were extracted by the BAμE device, desorbed by thermal desorption (TD), and analyzed by gas chromatography-mass spectrometry (GC-MS). The reproducibility of five BAμE devices prepared in parallel was less than 13.0% (expressed as relative standard deviation, RSD). The BAμE device could stand up to 30 extraction/desorption cycles without decrease of extraction efficiency. The results of method validation showed that the BAμE-TD/GC-MS method possessed wide linearity (0.05-50 μg/L or 0.05-20 μg/L), high correlation coefficients (> 0.9987), good precision (RSDs < 11.8%), low detection limits (0.005-0.013 μg/L) and high enrichment factors (528-1410). Relative recoveries were in the range of 72.2-122.6% with RSDs between 0.1% and 10.5% for real water samples. These results proved that the proposed method was a good choice for determination of organic pollutants in water samples.

Trends in sensitive detection and rapid removal of sulfonamides: A review

Sulfonamides in environmental water, food, and feed are a major concern for both aquatic ecosystems and public health, because they may lead to the health risk of drug resistance. Thus, numerous sensitive detection and rapid removal methodologies have been established. This review summarizes the sample preparation techniques and instrumental methods used for sensitive detection of sulfonamides. Additionally, adsorption and photocatalysis for the rapid removal of sulfonamides are also discussed. This review provides a comprehensive perspective on future sulfonamide analyses that have good performance, and on the basic methods for the rapid removal of sulfonamides.

Carbon and Tin-Based Polyacrylonitrile Hybrid Architecture Solid Phase Microextraction Fiber for the Detection and Quantification of Antibiotic Compounds in Aqueous Environmental Systems

In this study, the detection and quantification of multiple classes of antibiotics in water matrices are proposed using a lab-made solid phase microextraction (SPME) fiber coupled with high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). The lab-made fiber was prepared using a graphene oxide (G), carbon nanotubes (C), and titanium dioxide (T) composite, namely GCT, with polyacrylonitrile (PAN) as supporting material. The detected antibiotics were enrofloxacin, sulfathiazole, erythromycin, and trimethoprim. The custom-made fiber was found to be superior compared with a commercial C18 fiber. The excellent reproducibility and lower intra-fiber relative standard deviations (RSDs 1.8% to 6.8%) and inter-fiber RSDs (4.5% to 8.8%) made it an ideal candidate for the detection of traces of antibiotics in real environmental samples. The proposed validated method provides a satisfactory limit of detection and good linear ranges with higher (>0.99) coefficient of determination in the aqueous system. Application of the method was made in different real water systems such as river, pond and tap water using the standard spiking method. Excellent sensitivity, reproducibility, lower amount of sample detection and higher recovery was found in a real water sample. Therefore, the extraction method was successfully applied to the detection and quantification of multiple classes of antibiotics in different aqueous systems with satisfactory results.

A pressurized liquid extraction approach followed by standard addition method and UPLC-MS/MS for a fast multiclass determination of antibiotics in a complex matrix

In this work a fast analytical method for the determination of macrolides, tetracyclines and fluoroquinolones in a compost originating from a mixture of sewage sludge, palm waste and grass was developed by ultra-high performance liquid chromatography coupled to mass spectrometry (U-HPLC/MS). Antibiotics were extracted from compost by using the accelerated solvent extraction (ASE). The chromatographic separation was carried out on a T3 Cortecs C18 column using a mobile phase gradient mixture of water acidified with 1% of formic acid and acetonitrile. Recoveries of 24-30%, 53-93%, 33-57%, 69-135% and 100-171% were obtained for roxithromycin (ROX), chlortetracycline (CTC), oxytetracycline (OTC), enrofloxacin (ENR) and ciprofloxacin (CIP), respectively. As the most part of antibiotics showed significant matrix effect (ME), the method was validated using the standard addition method (SAM) to correct the observed ME. Instrumental variation, of LC/MS system, showed that 93.75% of the relative standard deviation (RSD %) are below 15%, although the organic load of extracts. This analytical method was applied to assess the fate of antibiotics during composting. Two composting experiments were conducted separately after spiking sludge at 2 different concentrations levels. The resulting elimination rates were of 52-76, 69-100, 100 and 24-50% for ROX, CTC, OTC and CIP, respectively. These results suggest that composting process contributes to the removal of residuals concentrations of macrolides and tetracyclines while the fluoroquinolones persist in the final compost product.

Enhanced magnetic ionic liquid-based dispersive liquid-liquid microextraction of triazines and sulfonamides through a one-pot, pH-modulated approach

In this study, an enhanced variant of magnetic ionic liquid (MIL)-based dispersive liquid-liquid microextraction is put forward. The procedure combines a water insoluble solid support and the [P₆₆₆₁₄⁺][Dy(III)(hfacac)₄^-] MIL, in a one-pot, pH-modulated procedure for microextraction of triazines (TZs) and sulfonamides (SAs). The solid supporting material was mixed with the MIL to overcome difficulties concerning the weighing of MIL and to control the uniform dispersion of the MIL, rendering the whole extraction procedure more reproducible. The pH-modulation during extraction step makes possible the one-pot extraction of SAs and TZs, from a single sample, in 15 min. Overall, the new analytical method developed enjoys the benefits of sensitivity (limits of quantification: 0.034-0.091 μg L^-1) and precision (relative standard deviation: 5.2-8.1%), while good recoveries (i.e., 89-101%) were achieved from lake water and effluent from a municipal wastewater treatment plant. Owing to all of the above, the new procedure can be used to determine the concentrations of SAs and TZs at levels below the maximum residue limits.

New-generation bar adsorptive microextraction (BAμE) devices for a better eco-user-friendly analytical approach-Application for the determination of antidepressant pharmaceuticals in biological fluids

The present contribution aims to design new-generation bar adsorptive microextraction (BAμE) devices that promote an innovative and much better user-friendly analytical approach. The novel BAμE devices were lab-made prepared having smaller dimensions by using flexible nylon-based supports (7.5 × 1.0 mm) coated with convenient sorbents (≈ 0.5 mg). This novel advance allows effective microextraction and back-extraction ('only single liquid desorption step') stages as well as interfacing enhancement with the instrumental systems dedicated for routine analysis. To evaluate the achievements of these improvements, four antidepressant agents (bupropion, citalopram, amitriptyline and trazodone) were used as model compounds in aqueous media combined with liquid chromatography (LC) systems. By using an N-vinylpyrrolidone based-polymer phase good selectivity and efficiency were obtained. Assays performed on 25 mL spiked aqueous samples, yielded average recoveries in between 67.8 ± 12.4% (bupropion) and 88.3 ± 12.1% (citalopram), under optimized experimental conditions. The analytical performance also showed convenient precision (RSD < 12%) and detection limits (50 ng L^-1), as well as linear dynamic ranges (160-2000 ng L^-1) with suitable determination coefficients (r² > 0.9820). The application of the proposed analytical approach on biological fluids showed negligible matrix effects by using the standard addition methodology. From the data obtained, the new-generation BAμE devices presented herein provide an innovative and robust analytical cycle, are simple to prepare, cost-effective, user-friendly and compatible with the current LC autosampler systems. Furthermore, the novel devices were designed to be disposable and used together with negligible amounts of organic solvents (100 μL) during back-extraction, in compliance with the green analytical chemistry principles. In short, the new-generation BAμE devices showed to be an eco-user-friendly approach for trace analysis of priority compounds in biological fluids and a versatile alternative over other well-stablished sorption-based microextraction techniques.