Chemistry and Materials Science

Abstract: Helichrysum italicum is a Mediterranean medicinal plant whose phloroglucinol (PG) α-pyrones constitute a structurally distinctive and pharmacologically relevant metabolite class, yet no systematic high-resolution mass spectrometric (HRMS) study has comprehensively characterized them. In this study, the acetone extract of inflorescences from Helichrysum italicum (Roth) G. Don was profiled by UHPLC–Orbitrap–MS in negative ion mode using full-scan and data-dependent MS/MS acquisition; exact-mass elemental composition assignment and HCD fragmentation analysis were combined with unsupervised clustering of fragment-ion and neutral-loss intensity matrices, validated against a manually curated annotation table using the adjusted Rand index (ARI) and cluster purity. From a total of 59 annotated compounds, 23 corresponded to known PG-α-pyrones previously reported from Helichrysum and 36 represented structures not previously described from the genus. Diagnostic fragment ions (FIs) and neutral losses (NLs) were established for identifying specific substituents of the α-pyrone and PG moieties. Semi-quantification gave a total PG-α-pyrone content of 0.019% dry weight, dominated by arzanol. This study establishes a UHPLC–HRMS framework for profiling phloroglucinol α-pyrone derivatives and confirms H. italicum as a rich source of this class.

Abstract: The increasing occurrence of antibiotic residues in aquatic environments poses significant risks to ecosystem integrity and public health, necessitating the development of rapid, sensitive, and portable analytical technologies. Herein, a MXene-supported dual single-atom Fe–Co nanozyme nanocomposite (FeCo-SA/MXene) is proposed as a high-performance electrocatalytic platform for the ultrasensitive electrochemical detection of antibiotic contaminants in water. The nanocomposite integrates the exceptional electrical conductivity and abundant surface functionalities of Ti₃C₂Tₓ MXene with atomically dispersed Fe–N₄ and Co–N₄ catalytic sites, enabling accelerated electron transfer and enhanced electrocatalytic activity. The structural characterization confirmed successful formation of isolated Fe–Co active sites without detectable metal nanoparticles, while electrochemical impedance spectroscopy indicated a substantial reduction in charge-transfer resistance from 185 Ω for the bare glassy carbon electrode to 26 Ω after FeCo-SA/MXene modification, accompanied by a 3.5-fold increase in electrochemically active surface area. The proposed sensor exhibited wide linear detection ranges of 0.5 nM–100 μM for tetracycline, 1 nM–80 μM for ciprofloxacin, 2 nM–100 μM for sulfamethoxazole, and 5 nM–120 μM for chloramphenicol, with corresponding detection limits of 0.12, 0.28, 0.45, and 0.83 nM, respectively. The sensor further demonstrated excellent selectivity against common interfering species, retained 96% of its initial response after 30 consecutive measurements and 94% after 4 weeks of storage, and achieved recoveries of 95.9–103.1% with relative standard deviations below 3.5% in environmental water samples. These findings demonstrate the potential of FeCo-SA/MXene nanozyme nanocomposites as a promising platform for developing next-generation electrochemical sensors for rapid, ultrasensitive, and reliable monitoring of emerging antibiotic contaminants in aquatic environments.

Abstract: Plants of the genus Crataegus have been used in traditional medicine to treat different health conditions, mainly cardiovascular diseases. Standardized extracts from this genus are marketed in Europe and Asia for the treatment of heart failure. In recent years, our research group has demonstrated that Crataegus gracilior, C. rosei, and C. mexicana exert significant vasorelaxing effects and that their most abundant and vasorelaxant constituents are the triterpenic acids they contain. Therefore, an HPLC-DAD analytical method was developed to simultaneously identify and quantify euscaphic, maslinic, corosolic, oleanolic, and ursolic acids, the main chemical constituents of the leaves of these three Mexican Crataegus species. Euscaphic acid was found to be the main compound in both C. rosei and C. mexicana while ursolic acid in C. gracilior. Therefore, these two acids were selected as their most suitable chemical and pharmacological markers. Accordingly, the developed method was validated for the two acids following the ICH Q2(R1) and USP guidelines. This method can be used for quality control of any crude commercial drugs produced from these species in the future.

Abstract: Existing reviews on MNP removal from water rarely link adsorbent structural features to the molecular interactions governing removal performance. This review addresses this gap by examining MNP adsorption from a mechanism-oriented perspective, mapping six canonical interaction pathways across five adsorbent classes. Adsorption emerges as a system-dependent process governed by the interplay between polymer properties and surface chemistry rather than by the material alone. Interactions such as π–π stacking and hydrophobic affinity dominate for non-functionalised polymers on carbon-rich surfaces, while electrostatic forces and hydrogen bonding become more relevant for oxidised particles. Pore structure becomes significant when particle size and porosity match, whereas chemisorption provides a stronger and faster pathway in systems containing reactive metal sites. Across material classes, differences relate more closely to scalability and sustainability than to intrinsic adsorption capacity. Bio-based materials offer a favourable balance between performance and practical implementation, while more advanced systems provide greater control but remain limited by synthesis complexity. Importantly, laboratory capacities often overestimate real performance, and removal efficiency in complex matrices is a more reliable metric. Future progress will depend on improved standardisation, better integration with modelling, and validation under realistic conditions to support the transition from laboratory studies to practical applications.

Abstract: Quantitative fluorescence analysis of aromatic pollutants in aquatic environments is frequently compromised by the primary inner filter effect (PIFE) induced by coexisting chromophoric species. In order to address this challenge, we propose a multi-component concentration quantification correction model that integrates transmittance absorbance and lateral (90°) fluorescence intensity. By establishing a coupled model of the excitation light decay dynamics and fluorescence emission, where styrene was used as the target analyte and anthracene/phenanthrene played the role of representative interferents, the inherently nonlinear PIFE was transformed into a tractable linear regression problem. The experiment shows that: under the coexistence of anthracene and phenanthrene, the model reduces the detection deviation of styrene from 40-63% to within 10%, and the correction accuracy of the three-component mixed system is increased by 3-5 times.The model in this work provides a theoretical framework for fluorescence quantitative analysis in complex systems, and also offers a new method for high-precision online monitoring of aromatic organic pollutants.

Abstract: A ratiometric electrochemical sensor based on poly(neutral red)-silver nanorods-carbon nanotubes (PNR-AgNRs/CNTs) composite was constructed for rapid, sensitive, and an-ti-interference detection of histamine in crayfish (Procambarus clarkii). Silver nanorods (AgNRs) were synthesized via a liquid-phase reduction method using 2-mercaptobenzoic acid (2-MBA) as both reducing and stabilizing agent, and subse-quently composited with carbon nanotubes (CNTs) through ultrasonic dispersion to form a three-dimensional conductive network. Poly(neutral red) (PNR) was electro-chemically polymerized onto the AgNRs-CNTs modified glassy carbon electrode (GCE) surface via cyclic voltammetry, serving as an electrochemical signal probe. The resulting PNR-AgNRs-CNTs/GCE exhibited significantly enhanced electrochemical performance with approximately 5-fold increase in electrochemically active surface area compared to bare GCE. Histamine competitively inhibited the electrochemical signal of PNR without affecting the AgNRs signal, enabling ratiometric detection based on the current signal ratio (IPNR/IAgNRs). Under optimized conditions (pH 6.0, adsorption time 6 min, material loading 0.08 mg/cm²), the IPNR/IAgNRs ratio exhibited a good linear relationship with the logarithm of histamine concentration in the range of 1–150 μmol/L, with a linear equa-tion of I/I = −0.3152 ln(C) + 5.0613, correlation coefficient R² = 0.995, and detection limit of 0.16 μmol/L (S/N = 3). The sensor demonstrated excellent anti-interference ability against common interfering substances such as Na⁺, Ca²⁺, K⁺, PO₄³⁻, and NO₃⁻. The relative standard deviations (RSD) for continuous 8-day detection and 8 parallel electrodes were 2.56% and 1.28%, respectively, indicating superior stability and reproducibility. The spiked recoveries in crayfish samples ranged from 95.9% to 102.3% with RSD < 3%, showing no significant difference from the national standard method (GB 5009.208-2016). The developed sensor effectively eliminated interference from complex biological ma-trices through the dual-signal ratio strategy and solved the detection problem of hista-mine lacking direct electrochemical response, providing a new approach for rapid on-site detection of histamine in aquatic products.

Abstract: Levofloxacin (LVX) is a broad-spectrum antibiotic whose systemic administration can be limited by adverse effects and suboptimal drug levels at infection sites. Implantable drug-loaded meshes offer a promising strategy for localized, prolonged delivery. This study developed and validated a simple, rapid, and reliable high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method for quantifying LVX in rat blood to support the preclinical evaluation of a prolonged-release LVX-loaded polypropylene mesh. The method utilized a Zorbax SB-C18 column with an isocratic mobile phase of acetonitrile:0.1% orthophosphoric acid (80:20, v/v) at a flow rate of 1.4 mL/min, with detection at 296 nm. Validation according to ICH Q2(R2) guidelines demonstrated excellent linearity (R² = 0.999) over 1–8 µg/mL, accuracy (mean recovery 99.68%), and precision (intra- and inter-day CV < 0.3%). The limits of detection and quantification were 0.3 µg/mL and 1.0 µg/mL, respectively. The validated method was successfully applied to quantify LVX in rat plasma samples collected over 10 days post-implantation, confirming its suitability for pharmacokinetic studies of implant-based antibiotic delivery systems. This method provides a practical and robust analytical tool for routine preclinical assessment of LVX release and systemic exposure from localized delivery devices.

Abstract: Conductive carbon materials have attracted significant scientific and technological interest due to their exceptional electrical, mechanical, and chemical properties. Among them, graphitized carbon fibers and glassy carbon are widely used in electrochemical applications because of their high conductivity, large active surface area, chemical stability, and environmental compatibility. Their graphitic structure enables efficient electron transfer, while surface functionalization enhances adsorption capacity, catalytic activity, and electrochemical sensitivity. Graphitized carbon fibers, particularly polyacrylonitrile-based (PAN) fibers, exhibit excellent mechanical strength, thermal stability, and resistance in aggressive chemical environments, making them suitable for microelectrodes, sensors, fuel cells, and energy storage systems. This work also examines the modification of graphitized carbon fibers through oxidation processes and the attachment of functional molecules or metal layers in order to improve electrocatalytic performance. Special emphasis is placed on thin bismuth-film electrodes, which have emerged as environmentally friendly alternatives to mercury electrodes in electroanalysis. Bismuth-coated carbon substrates combine low toxicity, favorable stripping behavior, and high analytical sensitivity with the advantageous properties of carbon materials. Different fabrication methods, including ex-situ and in-situ electrodeposition, as well as the influence of coating morphology on electrochemical performance, are discussed. Furthermore, the applications of bismuth-modified electrodes in anodic and adsorptive stripping voltammetry for the determination of heavy metals in environmental, biological, and food samples are presented. The combination of graphitized carbon materials with bismuth films provides enhanced sensitivity, selectivity, conductivity, and stability, making these systems highly promising for advanced electrochemical sensing, catalysis, environmental monitoring, and sustainable energy technologies.

Abstract: Gas chromatography–mass spectrometry (GC–MS) is widely used to separate, identify, and semi-quantify volatile and derivatizable semi-volatile constituents (mono-/sesqui-terpenoids, phenylpropanoids, fatty-acid derivatives) that carry the discriminatory chemical information needed for authentication and quality control of traditional Chinese medicinal materials (TCMMs). To frame the methodological landscape rather than merely list components, this synthesis draws on peer-reviewed GC–MS / HS‑SPME works mainly indexed in PubMed, Web of Science, and Scopus (focusing on the last decade), using searches built around keyword clusters (GC–MS, volatile oil, TCM authentication/QC, processing) and prioritizing studies that report separation conditions, pretreatment rationale, identification confidence (spectral match + retention index), and chemometric discrimination. The covered evidence shows GC–MS reliability depends less on instrument prestige than on upstream choices: pretreatment selectivity and thermal bias govern which labile markers survive; co-elution and matrix effects require explicit deconvolution/alignment; and identification confidence needs RI anchoring and, where possible, standard cross-checks, while inconsistent validation reporting and GC's intrinsic inaccessibility of strongly polar non-volatiles remain the main bottlenecks. When framed as a separation-first workflow—integrating optimized pretreatment (distillation/SPME/SFE), derivatization strategies, and multivariate modelling—GC–MS delivers verifiable chemical fingerprints to track geographical, batch, and processing-induced changes, supporting more comparable, regulation-ready QC protocols for TCMMs.

Abstract: This study is a comparative evaluation of Rosmarinus officinalis L. extracts obtained through different extraction techniques such as supercritical CO₂ (SC‑CO₂), Soxhlet extraction (with and without ethanol), ethanol tinctures, oil-based tinctures, and hydro-distillation, with the aim of determining their phenolic composition and antioxidant potential. Rosemary samples from Durres area were collected in two periods: January and May 2025. Phenolic profiling was performed using LC–MS analysis, enabling the quantification of major bioactive compounds including caffeic acid, hesperidin, rosmarinic acid, luteolin, apigenin, carnosol, and carnosic acid. Antioxidant activity was assessed through three complementary assays: ABTS radical cation decolorization, DPPH radical scavenging, and FRAP reducing power, each calibrated using Trolox equivalents. The results demonstrated that SC‑CO₂ extraction produced extracts with the highest levels of lipophilic diterpenes, especially carnosic acid (up to ~445 mg/g) and carnosol, along with significant amounts of phenolic acids and flavonoids. SC‑CO₂ extracts exhibited the strongest antioxidant activity across all assays, with ABTS, DPPH, and FRAP values higher those of other extraction methods. Soxhlet extraction with water yielded intermediate phenolic levels and antioxidant activity, particularly enriching rosmarinic acid and selected flavonoids, whereas Soxhlet with ethanol, ethanol tinctures, and oil-based tinctures shown lower phenolic concentrations and minimal antioxidant performance. Hydro-distillates contained only trace amounts of phenolics and negligible antioxidant capacity. Seasonal effects were also evident, with extracts harvested in May generally presenting higher phytochemical content and antioxidant activity than those collected in January. The findings shown that SC‑CO₂ extraction was the most effective and selective method for producing phenolic-rich, antioxidant-potent rosemary extracts, with significant implications for nutraceutical, cosmetic, and food applications.

Abstract: Wear-metal monitoring is an important component of lubricant condition monitoring but commonly relies on elemental techniques such as inductively coupled plasma optical emission spectroscopy (ICP-OES), which require dedicated laboratory infrastructure and sample preparation. This study evaluates whether Fourier-transform infrared (FT-IR) spectra of used engine oils can be combined with partial least squares regression (PLS) to provide a rapid screening estimate of iron (Fe) concentration. Used petrol and diesel engine-oil samples were analyzed by FT-IR spectroscopy and ICP-OES. PLS models were developed using processed FT-IR spectra as predictor variables and ICP-OES-derived Fe concentrations as response variables. For petrol used oil samples, the optimized model employing 18 latent variables achieved a root mean squared error of 5.02 ppm and a coefficient of determination of 0.97 between measured and predicted Fe concentrations. Model loadings indicated contributions from spectral features associated with soot, oxidation, nitration, antioxidant depletion, and zinc dialkyldithiophosphate depletion. Combining petrol and diesel samples in a single model reduced predictive performance and increased uncertainty, indicating that their differing degradation pathways cannot be adequately represented by one common latent-variable model. The approach does not directly measure Fe and is not intended to replace elemental analysis. Instead, it provides a rapid, low-cost screening tool for identifying samples with potentially elevated wear-metal concentrations and prioritizing them for confirmatory analysis.

Abstract: Wastewater treatment is purely a water purification step that clarifies wastewater from industrial, agricultural and human generated wastes like dyes, pesticides, antibiotics and plastics and heavy metals to make it consumable for humans. Access to safe and clean drinking water is a fundamental right and therefore should be accounted foremost to fulfil ongoing demands. Contamination of water is often due to the presence of water pollutants above the threshold value as directed by different statuary bodies like Central Pollution Control Board (CPCB) in India, responsible for determining the minimum pollutant that should be present in wastewater and marked as safe for human intake. Some of the most peculiar pollutant present in amicable amount in wastewater are dyes, heavy metals, pesticides, antibiotics, volatile organic compounds (VOCs), inorganic ions, polyaromatic hydrocarbons (PAHs), pharmaceuticals, and personal care products (PPCPs), endocrine disruptors (EDCs), persistent organic pollutants (POPs) and radionuclides among others. These are the products of textile industries, home wastes, and agricultural wastes and leather industries to name a few that are directly discarded into the water bodies without proper pre-chemical treatment. In this paper, we have attempted to search and include the exhaustive list of Metal-Organic frameworks (MOFs) exhibiting exceptional degradation capability towards wastewater to achieve our Sustainable Development Goal 6 (SDG 6) of access of safe and pure drinking water to all. In countries like India, where the availability of safely managed drinking water is a bare minimum, compared to its other continental counterparts, measures should be taken to ensure the minimization of poor sanitation facilities, safely managed domestic and industrial wastewater, the presence of water bodies with good ambient water quality, changes in water efficiency over time, freshwater withdrawal as proportion of available freshwater resources and degree of integrated water resource management. We have actively discussed the synthesis of novel MOFs such as lignocellulosic materials, biochars, MOF-derived carbons, bimetallic MOFs and magnetic materials exhibiting fantastic degradation capacity to fulfil our needs to purify water. The surface characteristics of MOF material is also discussed to include morphology, structure, metal ligand interaction, porosity and stability. The properties, history, background, classification—based on origin, synthesis, factors affecting synthesis, trends of publishing on Metal organic framework (MOF) based wastewater treatment as well as contrast to overall application is also discussed in brevity. The statistics revolving around proportions of available freshwater, discussion of a few water contaminants in greater detail, their removal rates and also a subsequent attempt to automate the process of water cleaning to sustain the global water needs and challenges using Metal organic framework (MOF) research database like the one such as PubChem used for drug research. Key limitations include the stability of MOF, toxicity, costly purchase of chemical for Metal organic framework (MOF) synthesis and not all composites work equally on all the contaminants like selective degradation of organic pollutants and recyclability is a problem that should be addressed equally.

Abstract: Emerging pharmaceutical pollutants (EPPs) are increasingly detected in aquatic environments worldwide, raising significant ecological and public health concerns due to their persistence and potential bioactivity. This study quantified selected non‑steroidal anti‑inflammatory drugs (NSAIDs), antiretroviral drugs (ARVs), psychotropic drugs, and a lipid regulator in surface waters and wastewater treatment works (WWTWs) across the eThekwini Metropolitan Municipality, South Africa. Grab samples were collected from 10 strategically selected sites representing diverse urban, peri-urban, and township river systems. Extracts were analyzed using solid-phase extraction coupled with HPLC-PDA. The method achieved strong linearity (R² = 0.9979–0.9991), recoveries of 70–120%, and detection limits ranging from 0.63 µg/L (efavirenz) to 0.66 µg/L (gemfibrozil). Pharmaceuticals were detected at all sites, with concentrations ranging from 5.13 µg/L to 6.99 µg/L along various riverbanks. Several locations also exceeded thresholds indicative of high mixture toxicity. This study provides the first comprehensive dataset on pharmaceutical pollutants in township river systems of eThekwini, emphasizing the urgent need for improved wastewater treatment infrastructure and the implementation of mixture‑based environmental risk assessment frameworks.

Abstract:

An Ag|AgCl redox couple has been thought to work as a reversible reference electrode although metal dissolution often occurs irreversibly. This report examines the kinetics by means of ac–impedance of AgCl films at the Ag electrode. A brief result is that the reaction rate for conventional voltammetric currents is totally irreversible although it can be enhanced with a thickness of the AgCl film. According to the frequency–dependence of the imaginary admittance, the double layer capacitance is determined only by the geometrical area of the Ag–electrode to exhibit 140 mF cm^–2. This value is caused by the delocalized charge of AgCl dipoles rather than water dipoles. The charge transfer rate of AgCl + e^– « Ag + Cl^– was evaluated from the variation of the real admittance with the frequency to yield the charge transfer rate constant with the order of 10^–9 cm s^–1. The rate constants increased with the surface density (G) of the deposited AgCl in proportion to G^0.3. The fractional power of the increase indicates that the reaction should occur not only at the geometrical area of the Ag–electrode but also at fluctuated Ag–particles in electric connection with the Ag–electrode caused by percolation. The reversibility of Ag|AgCl can be realized at current densities smaller than 0.1 mA mm^–2, exemplified by 10 nA at a 0.3 mm disk. Then, Ag|AgCl can be used for a counter electrode at ultramicroelectrode techniques in a two–electrode system.

Abstract: Among the micropollutants of medium-depth waters in isolated inhabited areas, the inorganic ones deserve special attention: nitrate anion (NO₃⁻) and phosphate anions (HxPO4^⁻(3⁻x)). The individual removal of these anions from water is widely studied, with different methods being found: chemical, ion exchange or biological. This paper presents a membrane method for the simultaneous removal of nitrate anion and phosphate anions from dilute synthetic aqueous solutions. The developed method is nanofiltration using composite membranes made of cellulose acetate (CA) and silver nanoparticles (Agnp). The composite membranes were made by phase inversion of the dimethylformamide (DMF) solution containing the two components (CA–Agnp) on a polypropylene (PP) capillary fiber using deionized waster as a coagulant. The DMF solution of CA containing Agnp was obtained by dissolving black-and-white cinematographic films (exposed and unexposed to light). CA–Agnp–PP composite membranes were tested for the simultaneous removal of nitrate anion and phosphate anions from aqueous solution by nanofiltration at pressures ranging from 5 to 25 bars. A removal of over 98% of phosphate anions and more than 95% of nitrate anion was achieved. Fluxes of 10 L·m^⁻2·h^⁻1 were obtained for the working pressure of 15 atm, depending on the pH, flow rate and concentration of the feed water (feed solution). Variable parameters studied were also the concentration of CA and Agnp.

Abstract: The rise in the presence and identification of biorefractory pollutants, also known as emerging contaminants (ECs) like microplastics, in the environment has been notable in recent times, attributed to factors such as population growth, changes in lifestyle, and rapid industrialization. A variety of pollutant substances are necessitated suitable remediation. Bioelectrochemical systems (BESs) represent sustainable technologies that can be utilized. In the current bibliometric investigation, the connection between bioelectrochemistry and pollutants in the environment is examined. Data obtained from the Web of Science database were utilized for the bibliometric analysis employing VOSviewer and R. According to the results, a highly integrated and rapidly maturing research landscape, characterized by a clear transition from fundamental technological development to large-scale environmental applications. The study serves as the essential bridge between the two primary pillars of the field: sustainable energy recovery and environmental remediation. The keyword co-occurrence networks illustrate a sophisticated synergy where the oxidative biodegradation of organic pollutants is directly coupled with electricity generation. A key discovery is the inherent synergy between the biodegradation of pollutants and the generation of electricity, which characterizes the contemporary ‘waste-to-energy’ model.

Abstract: The present study aimed to evaluate the stability of volatile organic compounds (VOCs) in exhaled breath samples under different storage conditions (refrigeration at -20 °C vs. room temperature) and analysis times (0 h, 3 h, 6 h, 12 h). Alveolar exhaled breath samples were collected from 30 volunteers in 500 mL Tedlar® bags, followed by analysis using headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). The results showed the putative identification of 73 metabolites, 41 of which were common to both conditions. Pre-analytical storage of the samples at -20 °C significantly altered (p < 0.05) the stability of 33 of the 41 common VOCs analyzed. Specifically, refrigeration improved stability by reducing the coefficient of variation (CV) in 23 of these metabolites compared to samples kept at room temperature. Highly stable metabolites with a CV < 15% were found. A 90% loss of the analytical signal was observed 12 hours after sample collection, in contrast to the stability maintained in refrigerated samples. These findings highlight the influence of pre-analytical conditions on the integrity of volatile profiles, establishing immediate refrigeration as a fundamental step for the study of potential biomarkers present in breath. These results provide key criteria for the standardization of breathomics protocols.

Abstract: Al Qurayyat salt is a traditional salt product that has been historically used in northern Saudi Arabia for food preservation, seasoning, and domestic uses. The city of Al Qurayyat is famous for its salt and is known as the city of salt in Saudi Arabia due to the abundance of salt deposits in areas such as Etra and Kaf. Despite its daily use by locals, there is no scientific information available regarding its chemical composition, heavy metals and safety. In this preliminary study, we aimed to analyze the physicochemical properties and metal contents of Al Qurayyat salt (ETR) and compare it to a commercially known salt (SAS). ETR chemical analysis showed a purity of 98.179%, moisture content of 0.68%, insoluble matter of 0.25%, and sulphate concentration of 7400 mg/kg. As expected, Iodine was not detected in the ETR sample, suggesting that the salt is non-iodized. Mineral analysis showed the presence of calcium (27 mg/kg), magnesium (32 mg/kg), potassium (10 mg/kg), copper (0.21 mg/kg), mercury (0.03 mg/kg), lead (0.13 mg/kg), and arsenic (0.01 mg/kg), while cadmium and iron were not detected or below the limit of detection. Heavy metal concentrations was below commonly accepted safety limits for edible salts. These findings provide the first reported physicochemical characterization of Al Qurayyat salt and establish baseline data for future investigations regarding its mineral composition, potential health uses, safety, nutritional significance, and potential industrial or culinary applications.

Abstract: The development of highly sensitive fluorescence sensing materials has attracted much attention in recent years. In this study, a new two-dimensional porous europium metal-organic frameworks (EuMOFs) have been obtained. Studies have shown that EuMOFs is a stable, fast response, and highly sensitive fluorescence sensor for isoprocarb and levofloxacin (Lvx), which are closely related to food safety and human health. The limits of detection (LOD) for isoprocarb and Lvx are as low as 1.0 and 0.5 nM, respectively, which were much lower than the national standards (GB 28260-2011 for isoprocarb is 2.583 μM). EuMOFs can also achieve strong anti-interference detection of isoprocarb in apple peel and rice extract solution, and Lvx in real urine, with excellent detection stability in 0.01~9.0 nM. The recovery rates for isoprocarb and Lvx in real samples are in 99.12%~101.25%.

Abstract: A cornerstone in transferring a classical liquid chromatography (LC) ultraviolet/visible (UV/Vis) method into greener and sustainable analytical method should consider the safety and toxicology of the used organic solvent in the method. Organic solvent portions used in the mobile phase may be replaced by a green solvent that is ideally bio-based and biodegradable to increase the greenness of the method. However, the implementation of a new solvent for high performance liquid chromatography (HPLC-UV/Vis) requires consideration of its environmental and health impact, cost-effectiveness, user-friendliness, and impact on the analytical performance and suitability of its chromatographic method. Existing greenness, blueness, and redness metrics expressing whiteness for evaluating the comprehensive sustainability of methods after solvent replacement overlook the chromatographic suitability of the selected solvent, this may potentially lead to suboptimal solvent replacement and an incomplete view of its capabilities. In this work, the authors present a Universal Suitability and Sustainability Index (USSI), a sixteen-parameter scoring system that quantifies four main factors for complete evaluation of a new solvent for implementation in HPLC. This index is beyond the white analytical chemistry principle. The four main factors are chromatographic suitability, greenness, blueness, and redness. Three of these factors, are based on available tools and metrics to evaluate the environmental and practicability impact on the health, and the analytical performance of the method. The fourth factor is added as an important criterion to judge the suitability of the solvent for HPLC analysis and to give an overview about its analytical applicability. The new index has been used to evaluate traditional liquid chromatographic as well as green solvents-based methods to give a universal overview that aids users to drive a rapid impression on the weakness and strength aspects and makes it easier to judge the selection of the solvent and the evaluation of the overall method sustainability.