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1.
Int J Mol Sci ; 25(15)2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39125820

RESUMEN

The purpose of this Special Issue is to showcase the latest findings in fluorine chemistry [...].


Asunto(s)
Flúor , Flúor/química , Humanos
2.
Water Sci Technol ; 90(1): 32-44, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39007305

RESUMEN

Developing a feasible and low-cost strategy for the recovery of calcium fluoride efficiently from fluoride-containing wastewater is very essential for the recycle of fluoride resources. Herein, a modified lime precipitation method was employed to recover CaF2 from fluorinated wastewater using a special icy lime solution. Intriguingly, the highest F- removal was greater than 95% under the optimal condition, leaving a fluoride concentration from 200 to 8.64 mg/L, while the lime dosage was much lower than that of industry. Importantly, spherical-shaped CaF2 particles with a 93.47% purity and size smaller than 600 nm were recovered, which has a high potential for the production of hydrofluoric acid. Besides, the precipitation was significantly affected by Ca/F molar ratio, stirring time, temperature, and solution pH. Furthermore, the thermodynamics and kinetics were investigated in detail to reveal the crystallization process. As a result, the defluorination reaction followed the pseudo-second order reaction kinetics model. Also, CO2 in the air adversely influenced the CaF2 purity. Based on this facile method, a high lime utilization efficiency was applied to defluorination, which contributed to protecting the environment and saving costs. This study, therefore, provides a feasible approach for the green recovery of fluorine resources and has significance for related research.


Asunto(s)
Compuestos de Calcio , Fluoruro de Calcio , Flúor , Óxidos , Aguas Residuales , Fluoruro de Calcio/química , Aguas Residuales/química , Flúor/química , Compuestos de Calcio/química , Óxidos/química , Contaminantes Químicos del Agua/química , Eliminación de Residuos Líquidos/métodos , Fluoruros/química
3.
J Mater Chem B ; 12(29): 7090-7102, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38984662

RESUMEN

Magnetic resonance imaging (MRI) has emerged as a pivotal tool in contemporary medical diagnostics, offering non-invasive and high-resolution visualization of internal structures. Contrast agents are essential for enhancing MRI resolution, accurate lesion detection, and early pathology identification. While gadolinium-based contrast agents are widely used in clinics, safety concerns have prompted exploration of metal-free alternatives, including fluorine and nitroxide radical-based MRI contrast agents. Fluorine-containing compounds exhibit excellent MRI capabilities, with 19F MRI providing enhanced resolution and quantitative assessment. Nitroxide radicals, such as PROXYL and TEMPO, offer paramagnetic properties for MRI contrast. Despite their versatility, nitroxide radicals suffer from lower relaxivity values (r1) compared to gadolinium. Dual-modal imaging, combining 1H and 19F MRI, has gained prominence for its comprehensive insights into biological processes and disease states. However, existing dual-modal agents predominantly utilize gadolinium-organic ligands without incorporating nitroxide radicals. Here, we introduce a novel dual-modal MRI contrast agent (J-CA) featuring a Janus asymmetric nanostructure synthesized via seeded emulsion polymerization and post-modification. J-CA demonstrates excellent in vitro and in vivo performance in both 19F and 1H MRI, with a T2 relaxation time of 5 ms and an r1 value of 0.31 mM-1 s-1, ensuring dual-modal imaging capability. Moreover, J-CA exhibits superior biocompatibility and organ targeting, making it a promising candidate for precise lesion imaging and disease diagnosis. This work introduces a new avenue for metal-free dual-modal MRI, addressing safety concerns associated with traditional contrast agents.


Asunto(s)
Medios de Contraste , Imagen por Resonancia Magnética , Nanoestructuras , Polímeros , Medios de Contraste/química , Medios de Contraste/síntesis química , Imagen por Resonancia Magnética/métodos , Animales , Ratones , Nanoestructuras/química , Polímeros/química , Humanos , Flúor/química , Tamaño de la Partícula
4.
Chem Commun (Camb) ; 60(65): 8609-8612, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39046095

RESUMEN

The development and the use of fluorinated polyproline-type II (PPII) foldamers are still underexplored. Herein, trifluoromethyl pseudoprolines have been incorporated into polyproline backbones without affecting their PPII helicity. The ability of the trifluoromethyl groups to increase hydrophobicity and to act as 19F NMR probes is demonstrated. Moreover, the enzymatic stability and the non-cytotoxicity of these fluorinated foldamers make them valuable templates for use in medicinal chemistry.


Asunto(s)
Péptidos , Prolina , Péptidos/química , Prolina/química , Prolina/análogos & derivados , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Flúor/química , Estructura Molecular
5.
J Med Chem ; 67(15): 13231-13251, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39049433

RESUMEN

Increasing evidence has demonstrated that oxidative phosphorylation (OXPHOS) is closely associated with the progression of pancreatic cancer (PC). Given its central role in mitochondrial transcription, the human mitochondrial RNA polymerase (POLRMT) is a promising target for developing PC treatments. Herein, structure-activity relationship exploration led to the identification of compound S7, which was the first reported POLRMT inhibitor possessing single-digit nanomolar potency of inhibiting PC cells proliferation. Mechanistic studies showed that compound S7 exerted antiproliferative effects without affecting the cell cycle, apoptosis, mitochondrial membrane potential (MMP), or intracellular reactive oxygen species (ROS) levels specifically in MIA PaCa-2 cells. Notably, compound S7 inhibited tumor growth in MIA PaCa-2 xenograft tumor model with a tumor growth inhibition (TGI) rate of 64.52% demonstrating significant improvement compared to the positive control (44.80%). In conclusion, this work enriched SARs of POLRMT inhibitors, and compound S7 deserved further investigations of drug-likeness as a candidate for PC treatment.


Asunto(s)
Antineoplásicos , Proliferación Celular , Cumarinas , ARN Polimerasas Dirigidas por ADN , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Animales , Relación Estructura-Actividad , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Antineoplásicos/uso terapéutico , Cumarinas/farmacología , Cumarinas/química , Cumarinas/síntesis química , Cumarinas/uso terapéutico , Proliferación Celular/efectos de los fármacos , ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , ARN Polimerasas Dirigidas por ADN/metabolismo , Línea Celular Tumoral , Ratones , Ratones Desnudos , Flúor/química , Apoptosis/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/uso terapéutico , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Endogámicos BALB C , Ensayos de Selección de Medicamentos Antitumorales
6.
Eur J Med Chem ; 276: 116722, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39079309

RESUMEN

Fluorine possesses distinctive chemical characteristics, such as its strong electron-withdrawing ability and small atomic size, which render it an invaluable asset in the design and optimization of pharmaceuticals. The utilization of fluorine-enriched medications for combating cancer has emerged as a prominent approach in medicinal chemistry and drug discovery, offering improved clinical outcomes and enhanced pharmacological properties. This comprehensive review explores the synthetic approaches and clinical applications of approved 22 representative fluorinated anti-cancer drugs from 2019 to present, shedding light on their historical development, brand names, drug target activity, mechanism of action, preclinical pharmacodynamics, clinical efficacy, and toxicity. Additionally, the review provides an extensive analysis of the representative synthetic techniques employed. Overall, this review emphasizes the significance of incorporating fluorine chemistry into anti-cancer drug research while highlighting promising future prospects for exploring compounds enriched with fluorine in the battle against cancer.


Asunto(s)
Antineoplásicos , Flúor , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Flúor/química , Neoplasias/tratamiento farmacológico , Animales , Estructura Molecular
7.
Talanta ; 278: 126503, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38963976

RESUMEN

Triclosan (TCS), triclocarban (TCC), and chlorophenols (CPs) are broad-spectrum antibacterials widely used in dermatological and oral hygiene products, which could induce severe liver and intestine injuries. Hence, it is essential to establish a rapid and sensitive method to monitor TCS, TCC, and CPs in various organisms. In this work, fluorine-functionalized covalent organic framework (COF-F) was prepared by using 4,4',4''-(1,3,5-triazine-2,4,6-triyl)tri-aniline and 2,3,5,6-tetrafluoroterephthalaldehyde as two building units and employed as a solid phase microextraction (SPME) probe for the extraction of TCS, TCC and CPs. The COF-F possessed excellent hydrophobicity, a large specific surface area (1354.3 m2 g-1) and high uniform porosity (3.2 nm), which facilitated high selectivity and adsorption properties towards TCS, TCC, and CPs. Therefore, the as-prepared COF-F-SPME in combination with electrospray ionization mass spectrometry has been developed to provide fast and ultrasensitive detection of TCS, TCC, and CPs in biological samples. The established method demonstrated satisfactory linear ranges (0.01-100.00 µg L-1) and low limits of detection (0.003-0.040 µg L-1) for TCS, TCC and CPs. The developed method could be successfully applied to detect TCS, TCC and CPs in the liver and kidney tissues of mice, demonstrating the potential for the detection of chlorinated aromatic pollutants in the biological samples.


Asunto(s)
Carbanilidas , Clorofenoles , Microextracción en Fase Sólida , Espectrometría de Masa por Ionización de Electrospray , Triclosán , Animales , Microextracción en Fase Sólida/métodos , Triclosán/análisis , Triclosán/química , Carbanilidas/análisis , Ratones , Clorofenoles/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Flúor/química , Estructuras Metalorgánicas/química , Límite de Detección , Masculino
8.
Water Res ; 261: 122021, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38986280

RESUMEN

Membrane distillation (MD) equipped with omniphobic (non-wetting) membranes has found a niche in water reclamation from hypersaline industrial wastewater. Here, we examined the efficacy of non-fluorinated materials as surface coating agents for omniphobic MD membrane fabrication, and identified necessary mechanisms to attain a maximized wetting resistance using fluorine-free materials. We first prepared MD membranes with different surface chemistries using a series of linear alkylsilanes and polydimethylsiloxane (PDMS) as representative fluorine-free, low surface energy materials. Membranes modified with a longer chain alkylsilane exhibited a lower surface energy and demonstrated a greater wetting resistance in direct contact MD experiments using feedwaters of various surface tensions. Despite the nearly identical surface energy measured for the longest alkylsilane and PDMS, PDMS-modified membrane exhibited an extended antiwetting performance as compared to the membrane treated with the longest alkylsilane. To elucidate the source of the distinctive wetting resistance, we examined the nucleation and condensation kinetics on the surfaces with the different surface chemistries via environmental scanning electron microscopy. Our analysis suggests that the membranes treated with long chain alkylsilanes contain surface defects (i.e., hydrophilic regions) whereas the high mobility of the PDMS effectively minimizes the defect exposure, slowing down the condensation and subsequent surface wetting.


Asunto(s)
Aguas Residuales , Purificación del Agua , Humectabilidad , Aguas Residuales/química , Purificación del Agua/métodos , Dimetilpolisiloxanos/química , Flúor/química , Solución Salina/química , Interacciones Hidrofóbicas e Hidrofílicas , Destilación
9.
Environ Sci Pollut Res Int ; 31(36): 49267-49284, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39066942

RESUMEN

This research aimed to introduce a novel method for the valorization of mineral waste, focusing on the development of hydroxyapatite (HAP) as an effective and economical adsorbent for immobilizing fluoride ions (F-) in soil. Hydroxyapatites were produced through the reaction between potassium dihydrogen phosphate (KH2PO4) and calcium-abundant limestone soil (CLS). X-ray diffraction analyses revealed that the primary phases in HAPCLS were brushite (CaHPO5·2H2O) and hydroxyapatite (Ca10(PO4)6(OH)2). The FTIR spectra exhibited characteristics akin to natural HAP, including the presence of orthophosphate groups (PO43-), hydroxyl groups (OH-), and both A/B types of carbonates in the apatite structure. The morphology of the synthesized HAP, as observed through SEM-EDS, was consistent with that of phosphocalcic hydroxyapatite crystals. The EDS results indicated a Ca/P atomic ratio of 1.7 for HAPCLS, aligning closely with the typical hydroxyapatite stoichiometry (Ca/P = 1.67). The application of HAP to reduce fluoride (F-) levels in soil proved to be successful; introducing 1% of various HAP formulations reduced the fluoride concentration from 51.4 mg/kg in untreated soil to levels below the IWSI limit (10 mg/kg), achieving a reduction to 8.1 mg/kg for HAPCLS. The sequential extraction of fluoride demonstrated that after soil treatment, fluoride was predominantly removed from the residual fraction (Fraction 4) and was effectively sequestered by the hydroxyapatites (Ca10(PO4)6(OH)2) through anionic exchange with hydroxide ions (OH-), resulting in the formation of stable and insoluble fluorapatite (Ca10(PO4)6F2).


Asunto(s)
Durapatita , Flúor , Suelo , Durapatita/química , Flúor/química , Suelo/química , Contaminantes del Suelo/química , Minerales/química , Difracción de Rayos X , Adsorción
10.
J Phys Chem B ; 128(25): 5925-5934, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38886167

RESUMEN

Fluorine is an element renowned for its unique properties. Its powerful capability to modulate molecular properties makes it an attractive substituent for protein binding ligands; however, the rational design of fluorination can be challenging with effects on interactions and binding energies being difficult to predict. In this Perspective, we highlight how computational methods help us to understand the role of fluorine in protein-ligand binding with a focus on molecular simulation. We underline the importance of an accurate force field, present fluoride channels as a showcase for biomolecular interactions with fluorine, and discuss fluorine specific interactions like the ability to form hydrogen bonds and interactions with aryl groups. We put special emphasis on the disruption of water networks and entropic effects.


Asunto(s)
Halogenación , Enlace de Hidrógeno , Proteínas , Ligandos , Proteínas/química , Proteínas/metabolismo , Flúor/química , Unión Proteica , Simulación de Dinámica Molecular , Agua/química
11.
Int J Biol Macromol ; 273(Pt 1): 132783, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38825285

RESUMEN

In this study, a brand-new, easy, and environmentally friendly approach for chemically functionalizing 2,2,6,6-tetramethylpiperidinyloxyl radical (TEMPO)-oxidized cellulose nanofiber (TOCNF) to produce modified cellulose nanofiber (octadecylamine-citric acid-CNF) was proposed. Effects of octadecylamine (ODA)/TOCNF mass ratio on the chemical structure, morphology, surface hydrophobicity and oleophobicity were studied. According to Fourier transform infrared spectroscopy (FTIR) analysis, ODA was successfully grafted onto the TOCNF by simple citric acid (CA) esterification and amidation reactions. Scanning electron microscopy (SEM) showed that a new rough structure was formed on the ODA-CA-CNF surface. The water contact angle (WCA) and the castor oil contact angle (OCA) of the ODA-CA-CNF reached 139.6° and 130.6°, respectively. The high-grafting-amount ODA-CA-CNF was sprayed onto paper, and the OCA reached 118.4°, which indicated good oil-resistance performance. The low-grafting-amount ODA-CNF was applied in a pH-responsive indicator film, exhibiting a colour change in response to the pH level, which can be applied in smart food packaging. The ODA-CA-CNF with excellent water/oil-resistance properties and fluorine-free properties can replace petrochemical materials and can be used in the fields of fluorine-free oil-proof paper.


Asunto(s)
Celulosa , Óxidos N-Cíclicos , Interacciones Hidrofóbicas e Hidrofílicas , Nanofibras , Nanofibras/química , Celulosa/química , Óxidos N-Cíclicos/química , Aminas/química , Ácido Cítrico/química , Agua/química , Espectroscopía Infrarroja por Transformada de Fourier , Flúor/química , Propiedades de Superficie
12.
Molecules ; 29(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38930990

RESUMEN

This article reports a simple hydrothermal method for synthesizing nickel disulfide (NiS2) on the surface of fluorine-doped tin oxide (FTO) glass, followed by the deposition of 5 nm Au nanoparticles on the electrode surface by physical vapor deposition. This process ensures the uniform distribution of Au nanoparticles on the NiS2 surface to enhance its conductivity. Finally, an Au@NiS2-FTO electrochemical biosensor is obtained for the detection of dopamine (DA). The composite material is characterized using transmission electron microscopy (TEM), UV-Vis spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The electrochemical properties of the sensor are investigated using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and time current curves in a 0.1 M PBS solution (pH = 7.3). In the detection of DA, Au@NiS2-FTO exhibits a wide linear detection range (0.1~1000 µM), low detection limit (1 nM), and fast response time (0.1 s). After the addition of interfering substances, such as glucose, L-ascorbic acid, uric acid, CaCl2, NaCl, and KCl, the electrode potential remains relatively unchanged, demonstrating its strong anti-interference capability. It also demonstrates strong sensitivity and reproducibility. The obtained Au@NiS2-FTO provides a simple and easy-to-operate example for constructing nanometer catalysts with enzyme-like properties. These results provide a promising method utilizing Au coating to enhance the conductivity of transition metal sulfides.


Asunto(s)
Técnicas Biosensibles , Dopamina , Técnicas Electroquímicas , Oro , Nanopartículas del Metal , Níquel , Dopamina/análisis , Dopamina/química , Oro/química , Níquel/química , Técnicas Biosensibles/métodos , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Electrodos , Compuestos de Estaño/química , Límite de Detección , Reproducibilidad de los Resultados , Flúor/química
13.
Proc Natl Acad Sci U S A ; 121(25): e2322403121, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38865273

RESUMEN

Fluorine magnetic resonance imaging (19F-MRI) is particularly promising for biomedical applications owing to the absence of fluorine in most biological systems. However, its use has been limited by the lack of safe and water-soluble imaging agents with high fluorine contents and suitable relaxation properties. We report innovative 19F-MRI agents based on supramolecular dendrimers self-assembled by an amphiphilic dendrimer composed of a hydrophobic alkyl chain and a hydrophilic dendron. Specifically, this amphiphilic dendrimer bears multiple negatively charged terminals with high fluorine content, which effectively prevented intra- and intermolecular aggregation of fluorinated entities via electrostatic repulsion. This permitted high fluorine nuclei mobility alongside good water solubility with favorable relaxation properties for use in 19F-MRI. Importantly, the self-assembling 19F-MRI agent was able to encapsulate the near-infrared fluorescence (NIRF) agent DiR and the anticancer drug paclitaxel for multimodal 19F-MRI and NIRF imaging of and theranostics for pancreatic cancer, a deadly disease for which there remains no adequate early detection method or efficacious treatment. The 19F-MRI and multimodal 19F-MRI and NIRF imaging studies on human pancreatic cancer xenografts in mice confirmed the capability of both imaging modalities to specifically image the tumors and demonstrated the efficacy of the theranostic agent in cancer treatment, largely outperforming the clinical anticancer drug paclitaxel. Consequently, these dendrimer nanosystems constitute promising 19F-MRI agents for effective cancer management. This study offers a broad avenue to the construction of 19F-MRI agents and theranostics, exploiting self-assembling supramolecular dendrimer chemistry.


Asunto(s)
Dendrímeros , Flúor , Nanomedicina Teranóstica , Dendrímeros/química , Animales , Nanomedicina Teranóstica/métodos , Humanos , Ratones , Flúor/química , Paclitaxel/química , Paclitaxel/uso terapéutico , Imagen por Resonancia Magnética/métodos , Línea Celular Tumoral , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/terapia , Imagen por Resonancia Magnética con Fluor-19/métodos , Ratones Desnudos , Medios de Contraste/química
14.
Anal Chim Acta ; 1312: 342749, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38834263

RESUMEN

Carbon monoxide (CO) is an innate signaling molecule that can regulate immune responses and interact with crucial elements of the circadian clock. Moreover, pharmacologically, CO has been substantiated for its therapeutic advantages in animal models of diverse pathological conditions. Given that an excessive level of CO can be toxic, it is imperative to quantify the necessary amount for therapeutic use accurately. However, estimating gaseous CO is notably challenging. Therefore, novel techniques are essential to quantify CO in therapeutic applications and overcome this obstacle precisely. The classical Myoglobin (Mb) assay technique has been extensively used to determine the amount of CO-release from CO-releasing molecules (CORMs) within therapeutic contexts. Nevertheless, specific challenges arise when applying the Mb assay to evaluate CORMs featuring innovative molecular architectures. Here, we report a fluorinated photo-CORM (CORM-FBS) for the photo-induced CO-release. We employed the 19F NMR spectroscopy approach to monitor the release of CO as well as quantitative evaluation of CO release. This new 19F NMR approach opens immense opportunities for researchers to develop reliable techniques for identifying molecular structures, quantitative studies of drug metabolism, and monitoring the reaction process.


Asunto(s)
Monóxido de Carbono , Luz , Mioglobina , Monóxido de Carbono/análisis , Mioglobina/química , Espectroscopía de Resonancia Magnética/métodos , Flúor/química , Animales , Procesos Fotoquímicos
15.
J Environ Manage ; 362: 121340, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38824889

RESUMEN

Co-pyrolysis of biomass with phosphogypsum (PG) presents an effective strategy for facilitating the recycling of PG resources. However, it is crucial to note the environmental threats arising from the presence of Pb, Cr, Ni, and F in PG. This study investigated the effect of immobilization and transformation of four elements during co-pyrolysis with biomass and its components. The co-pyrolysis experiments were carried out in a tube furnace with a mixture of PG and corn stover (CS), cellulose (C), lignin (L), glucose (G). Co-pyrolysis occurred at varying temperatures (600 °C, 700 °C, 800 °C, and 900 °C) and different addition ratios (10%, 15%, and 20%). The results indicated that an increase in co-pyrolysis temperature was more conducive to the immobilization and transformation of harmful elements in PG, demonstrating significant efficacy in controlling F. Additionally, the addition of biomass components exerts a significant impact on inhibiting product toxicity, with small molecules such as glucose playing a prominent role in this process. The mechanism underlying the control of harmful elements during co-pyrolysis of PG and biomass was characterized by three main aspects. Firstly, biomass components have the potential to melt-encapsulate the harmful elements in PG, leading to precipitation. Secondly, the pyrolysis gas produced during the co-pyrolysis process contributes to the formation of a rich pore structure in the product. Finally, this process aids in transforming hazardous substances into less harmful forms and stabilizing these elements. The findings of this study are instrumental in optimizing the biomass and PG blend to mitigate the environmental impact of their co-pyrolysis products.


Asunto(s)
Biomasa , Sulfato de Calcio , Cromo , Flúor , Plomo , Níquel , Níquel/química , Cromo/química , Plomo/química , Flúor/química , Sulfato de Calcio/química , Fósforo/química , Zea mays
16.
Anal Chim Acta ; 1314: 342754, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38876512

RESUMEN

The unique properties of per- and polyfluoroalkyl substances (PFAS) have led to their extensive use in consumer products, including ski wax. Based on the risks associated with PFAS, and to align with PFAS regulations, the international ski federation (FIS) implemented a ban on products containing "C8 fluorocarbons/perfluorooctanoate (PFOA)" at all FIS events from the 2021/2022 season, leading manufactures to shift their formulations towards short-chain PFAS chemistries. To date, most studies characterising PFAS in ski waxes have measured a suite of individual substances using targeted analytical approaches. However, the fraction of total fluorine (TF) in the wax accounted for by these substances remains unclear. In this study, we sought to address this question by applying a multi-platform, fluorine mass balance approach to a total of 10 commercially available ski wax products. Analysis of TF by combustion ion chromatography (CIC) revealed concentrations of 1040-51700 µg F g-1 for the different fluorinated waxes. In comparison, extractable organic fluorine (EOF) determined in methanol extracts by CIC (and later confirmed by inductively-coupled plasma-mass spectrometry and 19F- nuclear magnetic resonance spectroscopy) ranged from 92 to 3160 µg g-1, accounting for only 3-8.8 % of total fluorine (TF). Further characterisation of extracts by cyclic ion mobility-mass spectrometry (IMS) revealed 15 individual PFAS with perfluoroalkyl carboxylic acid concentrations up to 33 µg F g-1, and 3 products exceeding the regulatory limit for PFOA (0.025 µg g-1) by a factor of up to 100. The sum of all PFAS accounted for only 0.01-1.0 % of EOF, implying a high percentage of unidentified PFAS, thus, pyrolysis gas chromatography-mass spectrometry was used to provide evidence of the nature of the non-extractable fluorine present in the ski wax products.


Asunto(s)
Flúor , Fluorocarburos , Ceras , Fluorocarburos/análisis , Fluorocarburos/química , Flúor/análisis , Flúor/química , Ceras/química , Ceras/análisis , Caprilatos/análisis , Caprilatos/química
17.
Anal Chem ; 96(26): 10827-10834, 2024 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-38885015

RESUMEN

Kidney diseases have become an important global health concern due to their high incidence, inefficient diagnosis, and poor prognosis. Devising direct methods, especially imaging means, to assess renal function is the key for better understanding the mechanisms of various kidney diseases and subsequent development of effective treatment. Herein, we developed a fluorinated ferrous chelate-based sensitive probe, 1,7-DO2A-Fe(II)-F18 (Probe 1), for 19F magnetic resonance imaging (MRI). This highly fluorinated probe (containing 18 chemically equivalent 19F atoms with a fluorine content at 35 wt %) achieves a 15-time enhancement in signal intensity compared with the fluorine-containing ligand alone due to the appropriately regulated 19F relaxation times by the ferrous ion, which significantly increases imaging sensitivity and reduces acquisition time. Owing to its high aqueous solubility, biostability, and biocompatibility, this probe could be rapidly cleared by kidneys, which provides a means for monitoring renal dysfunction via 19F MRI. With this probe, we accomplish in vivo imaging of the impaired renal dysfunction caused by various kidney diseases including acute kidney injury, unilateral ureteral obstruction, and renal fibrosis at different stages. Our study illustrates the promising potential of Probe 1 for in vivo real-time visualization of kidney dysfunction, which is beneficial for the study, diagnosis, and even stratification of different kidney diseases. Furthermore, the design strategy of our probe is inspiring for the development of more high-performance 19F MRI probes for monitoring various biological processes.


Asunto(s)
Halogenación , Animales , Ratones , Sondas Moleculares/química , Riñón/diagnóstico por imagen , Riñón/patología , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Compuestos Ferrosos/química , Imagen por Resonancia Magnética , Enfermedades Renales/diagnóstico por imagen , Imagen por Resonancia Magnética con Fluor-19/métodos , Flúor/química
18.
Inorg Chem ; 63(21): 9877-9887, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38748735

RESUMEN

19F parashift probes with paramagnetically shifted reporter nuclei provide attractive platforms to develop molecular imaging probes. These probes enable ratiometric detection of molecular disease markers using a direct detection technique. Here, we describe a series of trivalent lanthanide (Ln(III)) complexes that are structural analogues of the clinically approved MR contrast agent (CA) ProHance to obtain LnL 19F parashift probes. We evaluated trans-gadolinium paramagnetic lanthanides compared to diamagnetic YL for 19F chemical shift and relaxation rate enhancement. The paramagnetic contribution to chemical shift (δPCS) for paramagnetic LnL exhibited either shifts to lower frequency (δPCS < 0 for TbL, DyL, and HoL) or shifts to higher frequency (δPCS > 0 for ErL, TmL, and YbL) compared to YL 19F spectroscopic signal. Zero-echo time pulse sequences achieved 56-fold sensitivity enhancement for DyL over YL, while developing probe-specific pulse sequences with fast delay times and acquisition times achieved 0.6-fold enhancement in limit of detection for DyL. DyL provides an attractive platform to develop 19F parashift probes for ratiometric detection of enzymatic activity.


Asunto(s)
Elementos de la Serie de los Lantanoides , Elementos de la Serie de los Lantanoides/química , Estructura Molecular , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Imagen por Resonancia Magnética , Medios de Contraste/química , Flúor/química , Humanos
19.
PLoS One ; 19(5): e0302937, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38753637

RESUMEN

With increasing global awareness of soil health, attention must be paid to fluorine exposure in soils, which poses a threat to human health. Therefore, this study aimed to study the fluorine adsorption characteristics of swine manure and straw biochars and their impact on fluorine adsorption-desorption in soil with batch experiments. The biochar samples originated from high-temperature anaerobic cracking of swine manure (350°C, 500°C, and 650°C) and straw (500°C). Results indicated that the adsorption of soil fluorine reached adsorption equilibrium at around 4 h after the mixing of swine manure and straw biochar. Fluorine adsorption kinetics using these biochars conformed to the quasi-two-stage kinetic model. The fluorine adsorption kinetics for biochar-treated soils conformed to the double-constant equation and the Elovich equation, and the soil treated with straw biochar showed the fastest fluorine adsorption rate. The adsorption isotherms of fluorine for biochars and biochar-treated soils could be fitted by the isothermal adsorption model of Langmuir and Freundlich. The maximal equilibrium quantity of fluorine was 73.66 mg/g for swine manure biochar. The soil, adding with 2% of swine manure biochar achieved with showed at 650°C had the smallest adsorption. This study also shows that the adsorption of fluorine by biochar gradually decreased with the increase of pH. Comparing with other factors, the mixture pH with biochars added had a significant effect on fluorine adsorption. The decreased fluorine adsorption capacities for soils treated with swine manure and straw biochars were closely related to the increased pH in soils after adding biochars. Considering the fluorine threat in soil, this study provides a theoretical basis for the application of biochars on soil fluorine adsorption.


Asunto(s)
Carbón Orgánico , Flúor , Estiércol , Suelo , Estiércol/análisis , Carbón Orgánico/química , Flúor/química , Animales , Adsorción , Suelo/química , Porcinos , Cinética , Concentración de Iones de Hidrógeno , Contaminantes del Suelo/química
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124349, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38692107

RESUMEN

Fluorine (F) is a pivotal element in the formation of human dental and skeletal tissues, and the consumption of water and tea constitutes a significant source of fluoride intake. However, prolonged ingestion of water and tea with excessive fluoride content can lead to fluorosis, which poses a serious health hazard. In this manuscript, a novel turn-on fluorescent probe DCF synthesized by bis-coumarin and tert-butyldiphenylsilane (TBDPS) was introduced for detecting F- in potable water and tea infusions. By leveraging the unique chemical affinity between fluoride and silicon, F- triggers the silicon-oxygen bond cleavage in DCF, culminating in a conspicuous emission of yellow fluorescence. Validated through a succession of optical tests, this probe exhibits remarkable advantages in terms of superior selectivity, a low detection limit, a large Stokes shift, and robust interference resistance when detecting inorganic fluoride. Moreover, it can serve as portable test strips for on-site real-time identification and quantitative analysis of F-. Furthermore, the application of DCF for in-situ monitoring and imaging of F- in zebrafish and soybean root tissues proved its significant value for F- detection in both animal and plant systems. This probe potentially functions as an efficient instrument for delving into the toxic mechanisms of fluoride in physiological processes.


Asunto(s)
Cumarinas , Colorantes Fluorescentes , , Pez Cebra , Colorantes Fluorescentes/química , Animales , Cumarinas/química , Té/química , Agua Potable/análisis , Espectrometría de Fluorescencia/métodos , Flúor/análisis , Flúor/química , Fluoruros/análisis , Glycine max/química , Límite de Detección , Imagen Óptica/métodos
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