A Comparative Analysis of Cold Brew Coffee Aroma Using the Gas Chromatography-Olfactometry-Mass Spectrometry Technique: Headspace-Solid-Phase Extraction and Headspace Solid-Phase Microextraction Methods for the Extraction of Sensory-Active Compounds.

Coffee, one of the most widely consumed commodities globally, embodies a sensory experience deeply rooted in social, cultural, and hedonic contexts. The cold brew (CB) method, characterized by cold extraction, is a refreshing and unique alternative to traditional coffee. Despite its growing popularity, CB lacks defined preparation parameters and comprehensive analysis of its aromatic composition. In this study, we aimed to obtain a representative extract of the volatile matrix of CB and characterize the aroma of sensory-active compounds using advanced techniques such as headspace-solid-phase Microextraction (HS-SPME) and headspace-solid-phase extraction (HS-SPE) for volatile compound extraction, followed by gas chromatography-olfactometry-mass Spectrometry (GC-O-MS) for compound identification. Optimization of the HS-SPME parameters resulted in the identification of 36 compounds, whereas HS-SPE identified 28 compounds, which included both complementary and similar compounds. In HS-SPME, 15 compounds exhibited sensory activity with descriptors such as floral, caramel, sweet, and almond, whereas seven exhibited sensory activity with descriptors such as chocolate, floral, coffee, and caramel. This comprehensive approach to HS-SPME and HS-SPE aroma extraction with GC-O-MS offers an efficient methodology for characterizing the aroma profile of CB, paving the way for future research and quality standards for this innovative coffee beverage.

Investigating the etiology of Haff disease: Optimization and validation of a sensitive LC-MS/MS method for palytoxins analysis in directly associated freshwater and marine food samples from Brazil.

Haff disease typically develops after eating contaminated marine or freshwater species, especially fish. Despite still having an unknown etiology, recent reports have suggested its possible correlation with palytoxins. Therefore, the present work aimed to optimize and perform a validation of a sensitive method using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) for the analysis of palytoxin and some of its analogs, with the main purpose of investigating their presence in marine and freshwater food samples associated with Haff disease in Brazil. The method optimization was performed using a central composite rotatable design and fish samples fortified with the palytoxin standard. Then, the optimized method was validated for different food matrices, including freshwater and marine fish, mollusks, and crustaceans. The sample preparation involved a solid-liquid extraction using methanol and water, solid-phase extraction using Strata-X cartridges, and on-column palytoxin oxidation. The detection of the main oxidized fragments (amino and amide aldehydes) was achieved by LC-MS/MS with electrospray ionization in positive mode, using a C18 column, as well as acetonitrile and water as mobile phases, both acidified with 0.1 % of formic acid. After optimization and validation, the etiological investigation involved the analysis of 16 Brazilian Haff disease-related food samples (in natura and leftover meals) from 2022. The method was demonstrated to be appropriate for quantitative analysis of freshwater and marine species. So far, it has proven to be one of the most sensitive methods related to palytoxin detection (LOD 10 µg/kg), being able to work in a range that includes the provisional ingestion limit (30 µg/kg). Regarding the Haff disease-related samples analysis, there is a strong indication of palytoxin contamination since the amino aldehyde (common fragment for all palytoxins) was detected in 15 of the 16 samples. Selected results were confirmed using liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS).

Chemical constituents of açai berry pulp (Euterpe oleracea Mart.) by LC-UV-BPSU/NMR and LC-UV-SPE/NMR.

The techniques LC-UV-BPSU and LC-UV-SPE/NMR were applied for the first time in the analysis of açai berry (Euterpe oleracea Mart.) pulp extracts. Those techniques allowed the identification of twenty-three metabolites: Valine (1), citric acid (2), tachioside (3), isotachioside (4), α-guaiacylglycerol (5), syringylglycerol (6), uridine (7), adenosine (8), dimethoxy-1,4-benzoquinone (9), koaburaside (10), protocatechuic acid (11), eurycorymboside B (12), 7',8'-dihydroxy-dihydrodehydroconiferyl alcohol-9-O-ß-D-glucopyranoside (13), orientin (14), homoorientin (15), dihydrokaempferol-3-glucoside (16), isolariciresinol-9'-O-ß-D-glucopyranoside (17), 5'-methoxyisolariciresinol-9'-O-ß-D-glucopyranoside (18), cyanidin-3-O-glucoside (19), cyandin-3-O-rutenoside (20), 9,12-octadecadienoic acid (Z,Z)-2-hydroxy-1-(hydroxymethyl) ethyl ester (21), linolenic acid (22), and 1,2-di-O-α-linolenoyl-3-O-ß-D-galactopyranosyl-sn-glycerol (23). In this plant, compounds 3, 4, 5, 6, 8, 10, 12, 17, 18, 21, and 23 are reported for the first time. All the structures were determined through extensive analyses of 1D and 2D NMR data, mass spectrometry, and comparison with published data. This methodology has proven to be an efficient alternative to the analysis of complex extracts containing a large variety of compounds.

Low-cost, facile droplet modification of screen-printed arrays for internally validated electrochemical detection of serum procalcitonin.

This manuscript presents the design and facile production of screen-printed arrays (SPAs) for the internally validated determination of raised levels of serum procalcitonin (PCT). The screen-printing methodology produced SPAs with six individual working electrodes that exhibit an inter-array reproducibility of 3.64% and 5.51% for the electrochemically active surface area and heterogenous electrochemical rate constant respectively. The SPAs were modified with antibodies specific for the detection of PCT through a facile methodology, where each stage simply uses droplets incubated on the surface, allowing for their mass-production. This platform was used for the detection of PCT, achieving a linear dynamic range between 1 and 10 ng mL-1 with a sensor sensitivity of 1.35 × 10-10 NIC%/ng mL-1. The SPA produced an intra- and inter-day %RSD of 4.00 and 5.05%, with a material cost of £1.14. Internally validated human serum results (3 sample measurements, 3 control) for raised levels of PCT (>2 ng mL-1) were obtained, with no interference effects seen from CRP and IL-6. This SPA platform has the potential to offer clinicians vital information to rapidly begin treatment for "query sepsis" patients while awaiting results from more lengthy remote laboratory testing methods. Analytical ranges tested make this an ideal approach for rapid testing in specific patient populations (such as neonates or critically ill patients) in which PCT ranges are inherently wider. Due to the facile modification methods, we predict this could be used for various analytes on a single array, or the array increased further to maintain the internal validation of the system.

Improved long-term outcomes with catheter-directed therapies over medical management in patients with submassive pulmonary embolism-a retrospective matched cohort study.

BACKGROUND: The benefit of catheter-directed therapy (CDT) for submassive pulmonary embolism (sPE) has been the subject of debate. We sought to determine the short- and long-term mortality and outcomes of CDT compared with anticoagulation for patients with sPE. METHODS: We performed a single healthcare network, multihospital, retrospective cohort study of hospitalizations for sPE from 2012 to 2019. sPE was defined as the presence of right heart strain or elevated biomarkers (troponin I or B-type natriuretic peptide). Patients with massive PE and those who had undergone systemic thrombolysis were excluded. The sPE groups included therapeutic anticoagulation alone or anticoagulation plus CDT (ie, thrombolysis or suction thrombectomy). The primary outcome was mortality at 1, 3, and 5 years. The other measured outcomes included PE-related death, short term mortality (30 days and 3 and 6 months), 30-day treatment-related complications (eg, bleeding, transfusion, stroke), chronic thromboembolic pulmonary hypertension, and 6-minute walk test at 1 year. After 1:1 nearest-neighbor propensity score matching, Kaplan-Meier survival plots were generated, and the treatment groups were compared using log-rank testing. We used Cox multivariate analysis to evaluate the outcomes after clustering at the hospital level, generating matched hazard ratios (mHRs) with associated 95% confidence intervals (CIs). RESULTS: Of 6746 sPE hospitalizations, the patients who had received CDT were younger (age, 58.9 ± 15.5 years vs 61.5 ± 17.4 years; P = .004), were more frequently White (92.5% vs 85.7%; P < .001), and had presented with a higher mean heart rate (104.6 bpm vs 94.9 bpm; P < .001), lower median systolic blood pressure (129 mm Hg vs 135 mm Hg; P < .001), and a greater incidence of right heart strain (79.2% vs 20.3%; P < .001). A total of 470 patients were matched, with 235 in the CDT group and 235 in the anticoagulation-only group. CDT was associated with a lower risk of mortality compared with anticoagulation at 1 year (7.6% vs 9.8%; mHR, 0.77; 95% CI, 0.65-0.92; P = .004), 3 years (11.1% vs 16.6%; mHR, 0.64; 95% CI, 0.55-0.73; P < .001), and 5 years (14.5% vs 19.1%; mHR, 0.71; 95% CI, 0.66-0.77; P < .001). Anticoagulation alone resulted in a greater incidence of PE-related deaths at 1, 3, and 5 years. The mortality at 30 days and 3 months was similar; however, CDT had resulted in better survival at 6 months (mHR, 0.81; 95% CI, 0.68-0.97; P = .02). No differences were found between the two groups in the incidence of bleeding complications at 30 days, development of chronic thromboembolic pulmonary hypertension, or the mean walking distance at 1 year. CONCLUSIONS: CDT plus anticoagulation for sPE was associated with improved long-term survival compared with anticoagulation alone, with a lower incidence of PE-related death and a low complication rate. CDT should be considered for select patients with sPE given its survival benefit.

The Ultratrace Determination of Fluoroquinolones in River Water Samples by an Online Solid-Phase Extraction Method Using a Molecularly Imprinted Polymer as a Selective Sorbent.

Fluoroquinolones (FQs) are broad-spectrum antibiotics widely used to treat animal and human infections. The use of FQs in these activities has increased the presence of antibiotics in wastewater and food, triggering antimicrobial resistance, which has severe consequences for human health. The detection of antibiotics residues in water and food samples has attracted much attention. Herein, we report the development of a highly sensitive online solid-phase extraction methodology based on a selective molecularly imprinted polymer (MIP) and fluorescent detection (HPLC-FLD) for the determination of FQs in water at low ng L−1 level concentration. Under the optimal conditions, good linearity was obtained ranging from 0.7 to 666 ng L−1 for 7 FQs, achieving limits of detection (LOD) in the low ng L−1 level and excellent precision. Recoveries ranged between 54 and 118% (RSD < 17%) for all the FQs tested. The method was applied to determining FQs in river water. These results demonstrated that the developed method is highly sensitive and selective.

Determination of polycyclic aromatic hydrocarbons in surface waters by high performance liquid chromatography previous to preconcentration through solid-phase extraction by using polymeric monoliths.

A simple, sensitive and reproducible solid-phase extraction method using plastic cartridges containing a monolithic sorbent (m-SPE), coupled to reverse phase liquid chromatography analysis, aiming to determine fifteen polycyclic aromatic hydrocarbons in surface water samples, was developed. The sorbent was easily prepared through a thermal polymerization reaction by using a mixture of n-butyl methacrylate as non-polar monomer and ethylene glycol dimethacrylate as crosslinker contained in a typical Polypropylene syringe cartridge. The effect of different parameters (type of hydrophobic monomer, elution solvent, sample volume, sorbent amount and sorbent load capacity) on the extraction efficiency was optimized. The optimal conditions were achieved by using n-butyl methacrylate as monomer, tetrahydrofurane (THF) as solvent for sorbent cleaning, THF:acetone (1:1) as elution solvent, 25.00 mL of sample volume, 600 µL of the polymerization mixture and 60 µg L-1 as sample loading capacity. Finally, the sorbent charge capacity, the reusability of the cartridges and the extraction efficiency of the m-SPE monolith, as compared with a typical C8 cartridge, were evaluated. Under the optimized experimental conditions, enrichment factors were between 76 and 103, relative recovery factors from 78 to 103%, accuracy values in the range of 58 to 98%, and inter-batch reproducibility values from between 2 and 10%, were obtained. The limits of detection and quantification were obtained by two different procedures: the signal to noise (S/N) ratios (3 and 10, respectively) and the IUPAC convention. The lowest LOD and LOQ values, obtained with the S/N ratios, were between 0.02 and 1.00 µg L-1, respectively whereas with the IUPAC convention the values were between 0.07 and 5 µg L-1. Using this procedure, several PAHs could be detected in the surface water sample taken from a river stream located in La Plata city (Buenos Aires Province, Argentina).

Wearable electrochemical biosensors to measure biomarkers with complex blood-to-sweat partition such as proteins and hormones.

Smart electronic devices based on micro-controllers, also referred to as fashion electronics, have raised wearable technology. These devices may process physiological information to facilitate the wearer's immediate biofeedback in close contact with the body surface. Standard market wearable devices detect observable features as gestures or skin conductivity. In contrast, the technology based on electrochemical biosensors requires a biomarker in close contact with both a biorecognition element and an electrode surface, where electron transfer phenomena occur. The noninvasiveness is pivotal for wearable technology; thus, one of the most common target tissues for real-time monitoring is the skin. Noninvasive biosensors formats may not be available for all analytes, such as several proteins and hormones, especially when devices are installed cutaneously to measure in the sweat. Processes like cutaneous transcytosis, the paracellular cell-cell unions, or even reuptake highly regulate the solutes content of the sweat. This review discusses recent advances on wearable devices based on electrochemical biosensors for biomarkers with a complex blood-to-sweat partition like proteins and some hormones, considering the commented release regulation mechanisms to the sweat. It highlights the challenges of wearable epidermal biosensors (WEBs) design and the possible solutions. Finally, it charts the path of future developments in the WEBs arena in converging/emerging digital technologies.

Dereplication of terpenes and phenolic compounds from Inga edulis extracts using HPLC-SPE-TT, RP-HPLC-PDA and NMR spectroscopy.

Inga edulis is traditionally used as anti-inflammatory and antidiarrheal and has been investigated as potential sources of biologically active natural products. In this study, dereplication strategy using HPLC-SPE-TT, RP-HPLC-PDA and NMR spectroscopy was employed, and this resulted in the identification of sixteen compounds from the leaves extract of I. edulis, including four triterpenes (lupeol, α-amirin, olean-18-ene acid and frideline), three flavonoids, eight phenolic acids, an anthocyanin derived from delphinidin-3-glycoside and a mixture of five acylated anthocyanins. The chemical identification was performed based on NMR data, chemosystematics aspects, UV spectra and by comparison with the retention time and UV spectra of authentic standards. The metabolic profile of the species indicated the presence of phenolic compounds as major constituents justifying its strong antioxidant potential performed in ß-carotene test. The techniques used have shown effective strategies for the early detection of active natural products from plant extracts, as these approaches are still crucially absent.[Formula: see text].

Solid Phase Extraction and Simultaneous Chromatographic Quantification of some Non-steroidal Anti-inflammatory Drug Residues; an Application in Pharmaceutical Industrial Wastewater Effluent

Abstract Two sensitive and selective methods were developed for the simultaneous determination of four commonly used non-steroidal anti-inflammatory drugs (NSAIDs), namely; paracetamol (PCM), diclofenac sodium (DCF), ibuprofen (IBP), and indomethacin (IND) in wastewater effluents. The first method used HPLC for the determination of the studied drugs using a mobile phase consisting of phosphate buffer (pH 3.0) and acetonitrile at a flow rate of 1 mL/min. in gradient elution mode and detection at 220 nm. The separation process was performed on BDS Hypersil Cyano column (250 x 4.6 mm, 5 µm). The second method was a TLC-densitometric one which was performed using n-Hexane: ethyl acetate: acetic acid in the ratio (6:3.5:0.5) as a developing system. The proposed chromatographic methods were successfully applied for the selective determination of the four studied drugs in simulated and real pharmaceutical wastewater samples after their solid-phase extraction

Sensitive determination of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol and complementary cannabinoids in hair using alkaline digestion and mixed-mode solid phase extraction followed by liquid-chromatography-tandem mass spectrometry.

Hair drug testing can be used for the evaluation of cannabis use with a large detection window, and is required for professional driving license granting in Brazil. A positive hair result for cannabis use requires quantification of the metabolite THC-COOH above the cutoff value of 0.2 ng/g. The achievement of such lower limit of quantification is challenging, particularly with the use of liquid chromatography coupled to triple quadrupole mass spectrometers (LC-MS/MS). In this study, a very sensitive LCMS/ MS assay for the simultaneous quantification of THC-COOH along with THC, CBD, and CBN was developed and validated. Sample preparation was based on hair hydrolysis, followed by selective ion-exchange solid-phase extraction. The extraction yield was 101.5-101.6% for THC-COOH, 92.3-97.4% for THC, 89.7-95.2% for CBN, and 104.9-121.1% for CBD. Internal standard corrected matrix effects were - 2.7 to - 1,1 for THCCOOH and - 11.5 to - 0.1% for the other analytes. The lower limit of quantification was 01 ng/g for THC-COOH and 25 ng/g for THC, CBD, and CBN. The assay fulfilled validation guidelines acceptance criteria. The measurement uncertainties were determined and the assay was ISO17025 accredited, being currently used in routine testing.

Clean-up Strategy for Dithiocarbamate Fungicide Determination in Soybean by GC-ITD-MS and GC-PFPD: Method Development and Validation.

Food matrices consist of many components with different physical and chemical properties that may influence instrumental robustness. The soybean contains fatty coextractives which may have a deleterious effect on the gas chromatography (GC) system. In this study, the efficiencies of PSA, C18OH, C18, silica, aluminum oxide, and Florisil, as dSPE clean-up sorbents, were evaluated by the high-performance liquid chromatography (HPLC) diode-array detector and evaporative light-scattering detector analysis. The dithiocarbamates in soybean samples are determined as CS2 using acidic hydrolysis and isooctane partitioning, followed by GC-PFPD and GC-ITD-MS analyses. The linearity of the analytical curves, the instrument limit of detection matrix effects, the trueness and precision, and the method limit of quantification (LOQ) were assessed in the validation study. Milled soybean was spiked with thiram solution at three concentration levels (corresponding to 0.05, 0.1, and 0.5 mg CS2 kg-1) for recovery determination. Silica appeared to be an effective and cheap sorbent to remove coextracted matrix components without causing any CS2 losses. Recoveries were in the range of 68-91%, with relative standard deviations ≤ 8.7%. The method LOQ was 0.05 mg CS2 kg-1, and both GC-ITD-MS and GC-PFPD systems appeared to be appropriate and complementary to determine dithiocarbamate residues in soybean extracts.

Removal of low-calorie sweeteners at five Brazilian wastewater treatment plants and their occurrence in surface water.

The consumption of low-calorie sweeteners (LCSs) such as acesulfame (ACE), sucralose (SUC), saccharin (SAC), cyclamate (CYC), aspartame (ASP), neotame (NEO), and stevioside (STV) is increasing worldwide to meet the demand for reduced-calorie foods and beverages. However, there are no consumption data available in Brazil, as well as their concentration in sewage and removal on wastewater treatment plants (WWTPs). In the present study, ACE, SUC, SAC, CYC, ASP, NEO, and STV were assessed at five WWTPs located in the metropolitan region of Campinas (São Paulo State, Brazil), in operation with different treatment processes. Surface water was also analyzed. Analyses were carried out by on-line solid-phase extraction ultra-high performance liquid chromatography-tandem mass spectrometry. The major points are the following: LCS concentrations in the influents ranged from 0.25 to 189 µg L-1 and followed the order CYC > ACE > SAC > SUC. NEO, ASP, and STV were not detected at any sampling site. Sweetener concentrations in the WWTP outputs differed mainly due to the different treatment setups employed. CYC and SAC were completely removed by biodegradation-based processes, while ACE removal was favored by the anaerobic-anoxic-aerobic process. SUC presented the highest concentration in the treated sewage, even at the WWTP operating with ultrafiltration membranes and therefore could be a marker compound for evaluation of the efficiency of removal of contaminants in WWTPs. Risk quotient estimation, using the PNEC and MEC values, indicated that the levels of the LCS reported here were harmless to the biota. The consumption of ACE, CYC, SAC, and SUC was estimated to be 2634 t year-1.

Occurrence of contaminants of emerging concern in surface waters from Paraopeba River Basin in Brazil: seasonal changes and risk assessment.

This study describes the application of gas chromatography coupled to mass spectrometry (GC-MS) to evaluate the occurrence of 12 CECs-contaminants of emerging concern (bisphenol A, diclofenac, 17ß-estradiol, estriol, estrone, 17α-ethinylestradiol, gemfibrozil, ibuprofen, naproxen, 4-nonylphenol, 4-octylphenol, and acetaminophen) in surface waters from Paraopeba River Basin, Minas Gerais State, Brazil. The analytical procedure was validated and applied to 60 surface water samples collected across four sampling campaigns along the upper and middle watershed. Methods for CECs determination involved sample filtration, and solid-phase extraction (SPE) with subsequent derivatization of the target compounds prior to their analysis by GC-MS. The LOQ varied from 3.6 to 14.4 ng/L and extraction recoveries ranged from 46.1 to 107.1% for the lowest spiked concentration level (10 ng/L). The results showed a profile of spatial distribution of compounds, as well as the influence of rainfall. Ibuprofen (1683.9 ng/L), bisphenol (1587.7 ng/L), and naproxen (938.4 ng/L) occurred in higher concentrations during the rainy season, whereas during the dry season, the concentrations of bisphenol (1057.7 ng/L), estriol (991.0 ng/L), and estrone (978.4 ng/L) were highlighted. The risk assessment of human exposure shows that for most contaminants, the concentration is well below the estimated thresholds for chronic toxicity from water intake. However, estradiol and 17α-ethinylestradiol showed concentrations in the same order of magnitude as the guide values estimated for babies.

In vivo anti-inflammatory activity of Fabaceae species extracts screened by a new ex vivo assay using human whole blood.

INTRODUCTION: Plants have been considered a promising source for discovering new compounds with pharmacological activities. The Fabaceae family comprises a large variety of species that produce substances with diverse therapeutic potential, including anti-inflammatory activity. The limitations of current anti-inflammatories generate the need to research new anti-inflammatory structures with higher efficacy as well as develop methods for screening multiple samples, reliably and ethically, to assess such therapeutic properties. OBJECTIVE: Validate and apply a quantification method for prostaglandin E2 (PGE2 ) production from an ex vivo assay in human blood in order to screen anti-inflammatory activity present in many Fabaceae species extracts. METHODS: Human blood was incubated with extracts from 47 Fabaceae species. After lipopolysaccharide (LPS)-induced inflammation, PGE2 was quantified in the plasma by liquid chromatography with tandem mass spectrometry (LC-MS/MS). The extracts that presented PGE2 production inhibition were further assessed through in vivo assay and then chemically characterised through an analysis of ultra-performance liquid chromatography electrospray ionisation quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-QTOF-MS2 ) data. RESULTS: The new ex vivo anti-inflammatory assay showed that five out of the 47 Fabaceae species inhibited PGE2 production. Results from an in vivo assay and the metabolic profile of the active extracts supported the anti-inflammatory potential of four species. CONCLUSION: The quantification method for PGE2 demonstrated fast, sensitive, precise, and accurate results. The new ex vivo anti-inflammatory assay comprised a great, reliable, and ethical approach for the screening of a large number of samples before an in vivo bioassay. Additionally, the four active extracts in both ex vivo and in vivo assays may be useful for the development of more efficient anti-inflammatory drugs.

Rationally designed dipicolinate-functionalized silica for highly efficient recovery of rare-earth elements from e-waste.

Composition of the immobilized layer plays a crucial role in metal adsorption properties of complexing organo-mineral materials. Ignoring the specific features of chemical reactions on solid surface can lead to a significant deterioration in the target properties of the resulted materials. In this research we demonstrated that rationally designed surface-assembling synthesis of organo-silica with covalently immobilized fragments of dipicolinic acid (DPA) resulted in the adsorbent that is capable quantitively recover almost all Rare Earth elements (REEs) from multielement solution with pH > 1.7. In ten consecutive adsorption/desorption cycles no noticeable loss of its efficiency was found, with a mean value of REEs recovery larger than 97%. The adsorbent has been used to recover REEs from model solutions (22 metal ions in 0.5 mol L-1 NaCl) and real leaching solution of waste of fluorescent lamps. It was demonstrated that even 3200-fold excess of Fe and Cu ions only slightly reduces REEs recovery. The adsorbent is capable to recover above 80% of all (except La) REEs from acidic leaching solution from fluorescent lamps with enrichment factors above 600. After adsorption of Eu3+ and Tb3+, the resulting materials exhibited strong red and green luminescence, respectively, indicating chelating mechanism of REEs adsorption on SiO2-DPA.

Development of a green and efficient methodology for the heterocyclic aromatic amine determination in biomass samples generated from cigarette combustion and tobacco.

A green methodology was developed for the analysis of ten heterocyclic aromatic amines (HAAs) in biomass samples from cigarette combustion such as mainstream smoke, paper ashes, as well as tobacco and paper wraps. The cellulose filter used for sample collection was also evaluated. This strategy was based on ultrasound-assisted extraction (UAE) associated with a solid-phase extraction procedure employing multi-walled carbon nanotubes (MWCNTs-SPE) as a cleanup step followed by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Under optimal experimental conditions, the linearity of the method was in the range from 0.08 to 160 ng cig-1, with correlation coefficients (R2) higher than 0.991. The limits of detection resulted to be between 0.03 and 0.63 ng cig-1. Concentrations of the HAAs in the mainstream smoke were from 5.7 to 145.2 ng cig-1 and in paper ashes from 0.1 to 0.6 ng cig -1, while in tobacco were between 1.0 and 38.5 ng cig-1. Meanwhile, no HAA contribution was observed in the case of paper wraps and the filter used for sample collection. The knowledge of the presence and the concentration levels of the selected HAAs in each cigarette's physical component after its combustion is essential to understand the formation processes and contribution during cigarette burning. Besides, this is the first report about the presence of some HAAs in the proposed samples. Finally, a comparative study was employed to classify the sustainability of several recent approaches for HAA extraction from cigarette combustion samples using Green Certificate as a metric tool.

Evaluation of the QuEChERS method for the determination of phenolic compounds in yellow (Brassica alba), brown (Brassica juncea), and black (Brassica nigra) mustard seeds.

Studies about the phenolic composition of yellow (Brassica alba), brown (Brassica juncea), and black (Brassica nigra) mustard seeds are still scarce in the literature. Hence, this study describes, for the first time, the use of the QuEChERS extraction method followed by UHPLC-MS/MS analysis for phenolic compound determination in the seeds of these mustard species. Under the optimized extraction and analysis conditions, twenty-one phenolic compounds were evaluated. Six, eleven, and seven were found in B. alba, B. juncea, and B. nigra seeds, respectively. The most abundant phenolic compound was sinapic acid, which was found in amounts ranging from 44 to 82 times higher than the other major compounds found in the mustard seeds, ferulic, 4-hydroxybenzoic and protocatechuic acids. Overall, these results are an important contribution to the characterization of the phenolic composition of the three in natura mustard seeds species, and support future reliable phenolic compounds determination with the QuEChERS method.

Matrix effect challenges to quantify 2,4-D and fipronil in aquatic systems.

Fipronil and 2,4-D are two main pesticides of sugarcane cultivation in Brazil. While pesticides have helped to improve food quality and quantity, the continuous increase in usage has raised concerns over the unintended negative environmental impacts they introduce. Mesocosm systems are used as surrogate ecosystems to evaluate the fate, transport, and transformation of pesticides. Controlled experimental manipulations on mesocosms simulate the effects of stressors on the environment, in which the studies to evaluate effects on the living organisms and assess pesticide dynamics produce more realistic data than those obtained in the laboratory. However, analytical methods that follow mesocosm studies shall be robust enough towards sensitive variations in analyte concentration and matrix-induced effects of suppression or enhancement of analytical response. An analytical method using solid-phase extraction (SPE) along with liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed for simultaneous determination of fipronil, 2,4-D, and their respective transformation products in aquatic systems. The method presented instrument quantification limits from 0.1 to 10.0 ng mL-1 and recovery values from 14 to 101%, with a maximum relative standard deviation (RSD) value of 12%. In the matrix effect assessment, the majority of matrix proportions showed a statistically relevant matrix effect for all compounds (p < 0.05). The method was further applied to over 500 different samples from mesocosm systems during controlled pesticide application and conversion of pastureland into sugarcane cropland. 2,4-D and fipronil mesocosm concentrations varied from 5 ng L-1 to 1.6 mg L-1 and 0.3 ng L-1 to 56 µg L-1, respectively.

Selective solid-phase extraction of organophosphorus pesticides and their oxon-derivatives from water samples using molecularly imprinted polymer followed by high-performance liquid chromatography with UV detection.

A molecularly imprinted polymer was synthesized and characterized to be used as solid-phase extraction sorbent for simultaneous chlorpyrifos and diazinon and their oxon derivatives. Several imprinted polymers were prepared and evaluated in a retention study of these analytes compared with a non-printed polymer. Several parameters affecting the extraction of imprinted polymer such as washing solvent, composition and volume of the eluting solvent and sample volume, were also investigated. Under the optimum conditions, the developed method provided satisfactory limits of detection ranging between 0.07 µg L-1 to 0.12 µg L-1 and the material showed an excellent reusability (> 50 reuses). The method was applied to the extraction and preconcentration of these analytes in water samples. The average recoveries ranged from 79 ± 6 to 104 ± 3 %.