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1.
Methods Mol Biol ; 2825: 173-184, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38913309

RESUMEN

Multitarget fluorescence in situ hybridization (mFISH) is a technique that allows the detection of multiple target sequences on the same sample using spectrally distinct fluorophore labels. The mFISH approach is currently a useful assay in the oncologic field for the detection of predictive, prognostic, and diagnostic biomarkers. In this chapter, we summarize the application of mFISH in the identification of target genetic aberrations in formalin-fixed, paraffin-embedded (FFPE) tissue samples of several tumor types. We discuss the mFISH protocols in FFPE samples, the innovative multitarget probes used, and the critical issues related to their interpretation.


Asunto(s)
Hibridación Fluorescente in Situ , Neoplasias , Adhesión en Parafina , Hibridación Fluorescente in Situ/métodos , Humanos , Neoplasias/genética , Neoplasias/diagnóstico , Adhesión en Parafina/métodos , Fijación del Tejido/métodos , Biomarcadores de Tumor/genética , Formaldehído/química
2.
Biochemistry (Mosc) ; 89(4): 637-652, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38831501

RESUMEN

Molecular genetic analysis of tumor tissues is the most important step towards understanding the mechanisms of cancer development; it is also necessary for the choice of targeted therapy. The Hi-C (high-throughput chromatin conformation capture) technology can be used to detect various types of genomic variants, including balanced chromosomal rearrangements, such as inversions and translocations. We propose a modification of the Hi-C method for the analysis of chromatin contacts in formalin-fixed paraffin-embedded (FFPE) sections of tumor tissues. The developed protocol allows to generate high-quality Hi-C data and detect all types of chromosomal rearrangements. We have analyzed various databases to compile a comprehensive list of translocations that hold clinical importance for the targeted therapy selection. The practical value of molecular genetic testing is its ability to influence the treatment strategies and to provide prognostic insights. Detecting specific chromosomal rearrangements can guide the choice of the targeted therapies, which is a critical aspect of personalized medicine in oncology.


Asunto(s)
Formaldehído , Neoplasias , Adhesión en Parafina , Humanos , Neoplasias/genética , Neoplasias/patología , Formaldehído/química , Translocación Genética , Fijación del Tejido , Cromatina/genética , Cromatina/metabolismo , Cromatina/química
3.
Chemosphere ; 361: 142517, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38830464

RESUMEN

Indoor volatile formaldehyde is a serious health hazard. The development of low-temperature and efficient nonhomogeneous oxidation catalysts is crucial for protecting human health and the environment but is also quite challenging. Single-atom catalysts (SACs) with active centers and coordination environments that are precisely tunable at the atomic level exhibit excellent catalytic activity in many catalytic fields. Among two-dimensional materials, the nonmagnetic monolayer material g-C3N4 may be a good platform for loading single atoms. In this study, the effect of nitrogen defect formation on the charge distribution of g-C3N4 is discussed in detail using density functional theory (DFT) calculations. The effect of nitrogen defects on the activated molecular oxygen of Pt/C3N4 was systematically revealed by DFT calculations in combination with molecular orbital theory. Two typical reaction mechanisms for the catalytic oxidation of formaldehyde were proposed based on the Eley-Rideal (E-R) mechanism. Pt/C3N4-V3N was more advantageous for path 1, as determined by the activation energy barrier of the rate-determining step and product desorption. Finally, the active centers and chemical structures of Pt/C3N4 and Pt/C3N4-V3N were verified to have good stability at 375 K by determination of the migration energy barriers and ab initio molecular dynamics simulations. Therefore, the formation of N defects can effectively anchor single-atom Pt and provide additional active sites, which in turn activate molecular oxygen to efficiently catalyze the oxidation of formaldehyde. This study provides a better understanding of the mechanism of formaldehyde oxidation by single-atom Pt catalysts and a new idea for the development of Pt as well as other metal-based single-atom oxidation catalysts.


Asunto(s)
Teoría Funcional de la Densidad , Formaldehído , Oxidación-Reducción , Platino (Metal) , Formaldehído/química , Catálisis , Platino (Metal)/química , Compuestos de Nitrógeno/química , Simulación de Dinámica Molecular , Oxígeno/química , Grafito
4.
Chemosphere ; 361: 142530, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38851511

RESUMEN

Chiroptical sensing with real-time colorimetrical detection has been emerged as quantifiable properties, enantioselective responsiveness, and optical manipulation in environmental monitoring, food safety and other trace identification fields. However, the sensitivity of chiroptical sensing materials remains an immense challenge. Here, we report a dynamically crosslinking strategy to facilitate highly sensitive chiroptical sensing material. Chiral nematic cellulose nanocrystals (CNC) were co-assembled with amino acid by a two-step esterification, of which a precisely tunable helical pitch, a unique spiral conformation with hierarchical and numerous active sites in sensing performance could be trigged by dynamic covalent bond on amines. Such a CNC/amino acid chiral optics features an ultra-trace amount of 0.08 mg/m3 and a high sensitivity of 60 nm/(mg/m3) for formaldehyde gas at a molecule level detection, which is due to the three synergistic adsorption enhancement of dynamic covalent bonded interaction, hydrogen bonded interaction and van der Waals interaction. Meanwhile, an enhancement hierarchical adsorption of CNC/amino acid chiral materials can be readily representative to the precise helical pitch and colorimetrical switch for sensitive visualization reorganization.


Asunto(s)
Celulosa , Nanopartículas , Compuestos Orgánicos Volátiles , Celulosa/química , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/química , Nanopartículas/química , Monitoreo del Ambiente/métodos , Aminoácidos/análisis , Aminoácidos/química , Colorimetría/métodos , Estereoisomerismo , Formaldehído/química , Formaldehído/análisis , Adsorción
5.
Chemosphere ; 361: 142576, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38852628

RESUMEN

Photocatalytic degradation stands as a promising method for eliminating gas-phase pollutants, with the efficiency largely hinging on the capture of photogenerated electrons by oxygen. In this work, we synthesized a porous CeO2 single crystal cube with abundant oxygen vacancies as photocatalyst, employing urea as a pore-forming agent and for gas-phase formaldehyde degradation. Compared with the CeO2 cubes without pores, the porous ones were superior in specific surface area, akin to conventional CeO2 nanoparticles. The photocatalytic degradation for gas-phase formaldehyde on porous CeO2 cubes was significantly accelerated, of which degradation rate is 3.3 times and 2.1 times that of CeO2 cubes without pores and CeO2 nanoparticles, respectively. Photoelectric tests and DFT calculations revealed that this enhancement stemmed from facilitated oxygen adsorption due to pronounced oxygen vacancies. Consequently, the capture of photoelectrons by oxygen was promoted and its recombination with holes was suppressed, along with an accelerated generation of curial free radicals such as ·OH. This work reveals the pivotal role of surface oxygen vacancies in promoting adsorbed oxygen, proposing a viable strategy to enhance the photocatalytic degradation efficiency for gas-phase pollutants.


Asunto(s)
Cerio , Formaldehído , Oxígeno , Formaldehído/química , Cerio/química , Oxígeno/química , Adsorción , Porosidad , Catálisis , Gases/química , Contaminantes Atmosféricos/química
6.
Chemosphere ; 361: 142550, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38857633

RESUMEN

Materials Institute Lavoisier (MIL) metal organic frameworks (MOFs) are known for their potential to adsorb gaseous organic pollutants. This study explores the synergistic effects between the selection of central metals (e.g., titanium, iron, and aluminum) and the incorporation of -NH2 groups in terms of adsorption efficiency against gaseous formaldehyde (FA). A group of the pristine MIL MOFs is synthesized using three different metals (i.e., titanium, iron, and aluminum) and terephthalic acid along with their NH2 derivatives using 2-aminoterephthalic acid. Among the pristine forms, MIL-125(Ti) achieves the highest FA adsorption capacity (Q) of 26.96 mg g-1 and a partition coefficient (PC) of 0.0898 mol kg-1 Pa-1. Further, amination significantly improves the FA adsorption potential of NH2-MIL-125(Ti) with a Q value of 91.22 mg g-1 (PC = 0.3038 mol kg-1 Pa-1). In situ diffuse reflectance infrared Fourier-transform spectroscopy reveals that the FA adsorption of plain MILs should be governed primarily by physisorption. In contrast, FA adsorption of NH2-MILs appears to be regulated by both physisorption and chemisorption, while the latter being affected mainly through FA-NH2 interactions (Schiff base reactions). These findings provide valuable insights into the utility of aminated MIL sorbents, possibly toward the efficient management of indoor air quality.


Asunto(s)
Contaminantes Atmosféricos , Formaldehído , Estructuras Metalorgánicas , Formaldehído/química , Adsorción , Estructuras Metalorgánicas/química , Contaminantes Atmosféricos/química , Titanio/química , Aluminio/química , Espectroscopía Infrarroja por Transformada de Fourier , Hierro/química
7.
Sci Rep ; 14(1): 12688, 2024 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-38830987

RESUMEN

Comprehensive characterization of protein networks in mounted brain tissue represents a major challenge in brain and neurodegenerative disease research. In this study, we develop a simple staining method, called TSWIFT, to iteratively stain pre-mounted formalin fixed, paraffin embedded (FFPE) brain sections, thus enabling high-dimensional sample phenotyping. We show that TSWIFT conserves tissue architecture and allows for relabeling a single mounted FFPE sample more than 10 times, even after prolonged storage at 4 °C. Our results establish TSWIFT as an efficient method to obtain integrated high-dimensional knowledge of cellular proteomes by analyzing mounted FFPE human brain tissue.


Asunto(s)
Encéfalo , Adhesión en Parafina , Coloración y Etiquetado , Humanos , Encéfalo/metabolismo , Adhesión en Parafina/métodos , Coloración y Etiquetado/métodos , Fijación del Tejido/métodos , Proteoma/análisis , Formaldehído/química , Proteómica/métodos
8.
Anal Methods ; 16(23): 3646-3653, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738568

RESUMEN

Formaldehyde (FA) is endogenously generated via fundamental biological processes in living systems. Aberrant FA homeostasis in subcellular microenvironments is implicated in numerous pathological conditions. Fluorescent probes for detecting FA in specific organelles are thus of great research interest. Herein, we present a modular strategy to construct diverse organelle-targeting FA probes by incorporating selective organelle-targeting moieties into the scaffold of a 1,8-naphthalimide-derived FA fluorescent probe. These probes react with FA through the 2-aza-Cope arrangement and exhibit highly selective fluorescence increases for detecting FA in aqueous solutions. Moreover, these organelle-targeting probes, i.e., FFP551-Nuc, FFP551-ER, FFP551-Mito, and FFP551-Lyso, allow selective localization and imaging of FA in the nucleus, endoplasmic reticulum, mitochondria, and lysosomes of live mammalian cells, respectively. Furthermore, FFP551-Nuc has been successfully employed to monitor changes of endogenous FA levels in the nucleus of live mammalian cells. Overall, these probes should represent new imaging tools for studying the biology and pathology associated with FA in different intracellular compartments.


Asunto(s)
Colorantes Fluorescentes , Formaldehído , Orgánulos , Colorantes Fluorescentes/química , Formaldehído/química , Humanos , Orgánulos/química , Orgánulos/metabolismo , Imagen Óptica/métodos , Células HeLa , Microscopía Fluorescente/métodos , Animales
9.
PLoS One ; 19(5): e0299557, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38718072

RESUMEN

The continued development in methylome analysis has enabled a more precise assessment of DNA methylation, but treatment of target tissue prior to analysis may affect DNA analysis. Prediction of age based on methylation levels in the genome (DNAmAge) has gained much interest in disease predisposition (biological age estimation), but also in chronological donor age estimation in crime case samples. Various epigenetic clocks were designed to predict the age. However, it remains unknown how the storage of the tissues affects the DNAmAge estimation. In this study, we investigated the storage method impact of DNAmAge by the comparing the DNAmAge of the two commonly used storage methods, freezing and formalin-fixation and paraffin-embedding (FFPE) to DNAmAge of fresh tissue. This was carried out by comparing paired heart tissue samples of fresh tissue, samples stored by freezing and FFPE to chronological age and whole blood samples from the same individuals. Illumina EPIC beadchip array was used for methylation analysis and the DNAmAge was evaluated with the following epigenetic clocks: Horvath, Hannum, Levine, Horvath skin+blood clock (Horvath2), PedBE, Wu, BLUP, EN, and TL. We observed differences in DNAmAge among the storage conditions. FFPE samples showed a lower DNAmAge compared to that of frozen and fresh samples. Additionally, the DNAmAge of the heart tissue was lower than that of the whole blood and the chronological age. This highlights caution when evaluating DNAmAge for FFPE samples as the results were underestimated compared with fresh and frozen tissue samples. Furthermore, the study also emphasizes the need for a DNAmAge model based on heart tissue samples for an accurate age estimation.


Asunto(s)
Metilación de ADN , Formaldehído , Miocardio , Adhesión en Parafina , Fijación del Tejido , Humanos , Adhesión en Parafina/métodos , Formaldehído/química , Miocardio/metabolismo , Fijación del Tejido/métodos , Masculino , Adulto , Femenino , Persona de Mediana Edad , Criopreservación/métodos , Adolescente , Anciano , Adulto Joven
10.
Methods Cell Biol ; 186: 213-231, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38705600

RESUMEN

Advancements in multiplexed tissue imaging technologies are vital in shaping our understanding of tissue microenvironmental influences in disease contexts. These technologies now allow us to relate the phenotype of individual cells to their higher-order roles in tissue organization and function. Multiplexed Ion Beam Imaging (MIBI) is one of such technologies, which uses metal isotope-labeled antibodies and secondary ion mass spectrometry (SIMS) to image more than 40 protein markers simultaneously within a single tissue section. Here, we describe an optimized MIBI workflow for high-plex analysis of Formalin-Fixed Paraffin-Embedded (FFPE) tissues following antigen retrieval, metal isotope-conjugated antibody staining, imaging using the MIBI instrument, and subsequent data processing and analysis. While this workflow is focused on imaging human FFPE samples using the MIBI, this workflow can be easily extended to model systems, biological questions, and multiplexed imaging modalities.


Asunto(s)
Adhesión en Parafina , Humanos , Adhesión en Parafina/métodos , Espectrometría de Masa de Ion Secundario/métodos , Fijación del Tejido/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Formaldehído/química
11.
Int J Mol Sci ; 25(10)2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38791537

RESUMEN

Many years of foundry practice and much more accurate analytical methods have shown that sands with organic binders, in addition to their many technological advantages, pose risks associated with the emission of many compounds, including harmful ones (e.g., formaldehyde, phenol, benzene, polycyclic aromatic hydrocarbons, and sulfur), arising during the pouring of liquid casting alloys into molds, their cooling, and knock-out. The aim of this research is to demonstrate the potential benefits of adopting inorganic binders in European iron foundries. This will improve the environmental and working conditions by introducing cleaner and more ecological production methods, while also ranking the tested binders studied in terms of their harmful content. The article pays special attention to the analysis of seven innovative inorganic binders and one organic binder, acting as a reference for emissions of gases from the BTEX (benzene, toluene, ethylbenzene, and xylenes) and PAHs (polycyclic aromatic hydrocarbons) groups and other compounds such as phenol, formaldehyde, and isocyanates (MDI and TDI) generated during the mold pouring process with liquid metals. The knowledge gained will, for the first time, enrich the database needed to update the Reference Document on The Best Available Techniques for the Smitheries and Foundries Industry (SF BREF).


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/química , Compuestos Inorgánicos/química , Metalurgia , Formaldehído/química
12.
Environ Sci Technol ; 58(19): 8372-8379, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38691628

RESUMEN

The development of highly efficient catalysts for formaldehyde (HCHO) oxidation is of significant interest for the improvement of indoor air quality. Up to 400 works relating to the catalytic oxidation of HCHO have been published to date; however, their analysis for collective inference through conventional literature search is still a challenging task. A machine learning (ML) framework was presented to predict catalyst performance from experimental descriptors based on an HCHO oxidation catalysts database. MnOx, CeO2, Co3O4, TiO2, FeOx, ZrO2, Al2O3, SiO2, and carbon-based catalysts with different promoters were compiled from the literature. Notably, 20 descriptors including reaction catalyst composition, reaction conditions, and catalyst physical properties were collected for data mining (2263 data points). Furthermore, the eXtreme Gradient Boosting algorithm was employed, which successfully predicted the conversion efficiency of HCHO with an R-square value of 0.81. Shapley additive analysis suggested Pt/MnO2 and Ag/Ce-Co3O4 exhibited excellent catalytic performance of HCHO oxidation based on the analysis of the entire database. Validated by experimental tests and theoretical simulations, the key descriptor identified by ML, i.e., the first promoter, was further described as metal-support interactions. This study highlights ML as a useful tool for database establishment and the catalyst rational design strategy based on the importance of analysis between experimental descriptors and the performance of complex catalytic systems.


Asunto(s)
Contaminación del Aire Interior , Formaldehído , Aprendizaje Automático , Oxidación-Reducción , Formaldehído/química , Catálisis
13.
Astrobiology ; 24(5): 489-497, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38696654

RESUMEN

Ribose is the defining sugar in ribonucleic acid (RNA), which is often proposed to have carried the genetic information and catalyzed the biological reactions of the first life on Earth. Thus, abiological processes that yield ribose under prebiotic conditions have been studied for decades. However, aqueous environments required for the formation of ribose from materials available in quantity under geologically reasonable models, where the ribose formed is not immediately destroyed, remain unclear. This is due in large part to the challenge of analysis of carbohydrates formed under a wide range of aqueous conditions. Thus, the formation of ribose on prebiotic Earth has sometimes been questioned. We investigated the quantitative effects of pH, temperature, cation, and the concentrations of formaldehyde and glycolaldehyde on the synthesis of diverse sugars, including ribose. The results suggest a range of conditions that produce ribose and that ribose could have formed in constrained aquifers on prebiotic Earth.


Asunto(s)
Formaldehído , Ribosa , Temperatura , Agua , Ribosa/química , Concentración de Iones de Hidrógeno , Agua/química , Formaldehído/química , Acetaldehído/química , Acetaldehído/análogos & derivados , Planeta Tierra , Origen de la Vida
14.
Environ Res ; 255: 119186, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38777297

RESUMEN

The removal of formaldehyde (FA) is vital for indoor air quality management in light of its carcinogenic propensity and adverse environmental impact. A series of copper manganite spinel structures (e.g., CuMn2O4) are prepared using the sol-gel combustion method and treated with reduction or oxidation pretreatment at 300 °C condition. Accordingly, CuMn2O4-O ("O" suffix for oxidation pre-treatment in air) is identified as the best performer to achieve 100% conversion (XFA) of FA (50 ppm) at 90 °C; its performance, if assessed in terms of reaction kinetic rate (r) at XFA = 10%, is 5.02E-03 mmol g-1 h-1. The FA removal performance increases systematically with decreases in flow rate, FA concentration, and relative humidity (RH) or with increases in bed mass. The reaction pathways and intermediates of FA catalytic oxidation on CuMn2O4-A are studied with density functional theory simulations, temperature-programmed characterization experiments, and in-situ diffuse reflectance infrared Fourier transform spectroscopy. The synergistic combination of large quantities of adsorbed oxygen (OA) species and oxidized metal species (e.g., Cu2+) contribute to the enhanced catalytic performance of CuMn2O4-O to oxidize FA into CO2 with the reaction intermediates of H2CO2 (DOM), HCOO-, and CO. The present study is expected to provide valuable insights into the thermocatalytic oxidation of FA over spinel CuMn2O4 materials and their catalytic performances in relation to the key process variables.


Asunto(s)
Cobre , Formaldehído , Formaldehído/química , Cobre/química , Catálisis , Contaminantes Atmosféricos/química , Contaminantes Atmosféricos/análisis , Oxidación-Reducción , Temperatura , Frío , Óxido de Aluminio , Óxido de Magnesio
15.
Environ Sci Technol ; 58(23): 10378-10387, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38805367

RESUMEN

Room temperature catalytic oxidation (RTCO) using non-noble metals has emerged as a highly promising technique for removal of formaldehyde (HCHO) under ambient conditions; however, non-noble catalysts still face the challenges related to poor water resistance and low stability under harsh conditions. In this study, we synthesized a series of layered double hydroxides (LDHs) incorporating various dual metals (MgAl, ZnAl, NiAl, NiFe, and NiTi) for formaldehyde oxidation at ambient temperature. Among the synthesized catalysts, the NiTi-LDH catalyst showed an HCHO removal efficiency and CO2 yield close to 100.0%, and exceptional water resistance and chemical stability on running 1300 min. The abundant hydroxyl groups in LDHs directly bonded with HCHO, leading to the production of CO2 and H2O, thus inhibiting the formation of CO, even in the absence of O2 and H2O. The coexistence of O2 effectively reduced the reaction barrier for H2O molecule dissociation, facilitating the formation of hydroxyl groups and their subsequent backfill on the catalyst surface. The mechanisms underlying the involvement and regeneration of hydroxyl groups in room temperature oxidation of formaldehyde were elucidated with the combined in situ DRIFTS, HCHO-TPD-MS, and DFT calculations. This work not only demonstrates the potential of LDH catalysts in environmental applications but also advances the understanding of the fundamental processes involved in room temperature oxidation of formaldehyde.


Asunto(s)
Formaldehído , Hidróxidos , Oxidación-Reducción , Temperatura , Formaldehído/química , Hidróxidos/química , Catálisis
16.
Environ Pollut ; 351: 124090, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38697249

RESUMEN

Indoor formaldehyde poses a significant carcinogenic risk to human health, making its removal imperative. Electro-Fenton degradation has emerged as a promising technology for addressing this concern. In the electro-Fenton system, ·OH is identified as the primary active species responsible for formaldehyde removal. Hence, its generation and utilization are pivotal for the system's effectiveness and economy. Experimental and quantum chemical methods were employed to investigate the effects and mechanisms of nitrogen doping on various aspects influencing ·OH generation and utilization. Results indicate that nitrogen doping synergistically enhances the generation and utilization of ·OH, leading to an improved formaldehyde removal efficiency in nitrogen-doped cathodic systems. The dominant nitrogen type influencing ·OH generation and utilization varies across different stages. Pyridinic nitrogen facilitates H2O2 adsorption through hydrogen bonding, while pyrrolic and graphitic nitrogen contribute to formaldehyde adsorption and catalyze the conversion of H2O2 to ·OH. Both pyridinic nitrogen and pyrrolic nitrogen boost the degradation of formaldehyde by ·OH. In comparison to the unmodified system, the modified system with NAC-GF/700C as cathode exhibits remarkable improvements. The formaldehyde removal efficiency has increased twofold, and energy consumption reduced by 73.45%. Furthermore, the system demonstrates excellent cyclic stability. These advancements can be attributed to the activation temperature, which leads to the appropriate types and high content of nitrogen elements in NAC-GF/700C. The research represents an important step towards more economical and efficient electro-Fenton technology for indoor formaldehyde removal.


Asunto(s)
Contaminación del Aire Interior , Carbono , Electrodos , Formaldehído , Peróxido de Hidrógeno , Formaldehído/química , Peróxido de Hidrógeno/química , Carbono/química , Radical Hidroxilo/química , Contaminantes Atmosféricos/química , Hierro/química , Adsorción
17.
ACS Appl Bio Mater ; 7(5): 3452-3459, 2024 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-38723150

RESUMEN

A two-photon nanoparticle probe was designed and developed based on the principle of intermolecular interaction of the aggregation-induced locally excited emission luminescence mechanism. The probe has the advantages of simple synthesis, convenient use, strong atomic economy, good biocompatibility, and photobleaching resistance. It can produce a specific and sensitive response to formaldehyde, help detect FA in normal cells and cancer cells, and is expected to become a specific detection probe for FA in vitro and in vivo.


Asunto(s)
Materiales Biocompatibles , Formaldehído , Ensayo de Materiales , Nanopartículas , Tamaño de la Partícula , Fotones , Formaldehído/química , Formaldehído/análisis , Humanos , Nanopartículas/química , Materiales Biocompatibles/química , Materiales Biocompatibles/síntesis química , Luminiscencia , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Estructura Molecular
18.
J Labelled Comp Radiopharm ; 67(7): 254-262, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38703027

RESUMEN

Reductive N-11C-methylation using [11C]formaldehyde and amines has been used to prepare N-11C-methylated compounds. However, the yields of the N-11C-methylated compounds are often insufficient. In this study, we developed an efficient method for base-free reductive N-11C-methylation that is applicable to a wide variety of substrates, including arylamines bearing electron-withdrawing and electron-donating substituents. A 2-picoline borane complex, which is a stable and mild reductant, was used. Dimethyl sulfoxide was used as the primary reaction solvent, and glacial acetic acid or aqueous acetic acid was used as a cosolvent. While reductive N-11C-methylation efficiently proceeded under anhydrous conditions in most cases, the addition of water to the reductive N-11C-methylation generally increased the yield of the N-11C-methylated compounds. Substrates with hydroxy, carboxyl, nitrile, nitro, ester, amide, and phenone moieties and amine salts were applicable to the reaction. This proposed method for reductive N-11C-methylation should be applicable to a wide variety of substrates, including thermo-labile and base-sensitive compounds because the reaction was performed under relatively mild conditions (70°C) without the need for a base.


Asunto(s)
Aminas , Radioisótopos de Carbono , Formaldehído , Hidrocarburos Yodados , Metilación , Radioisótopos de Carbono/química , Aminas/química , Formaldehído/química , Hidrocarburos Yodados/química , Oxidación-Reducción
19.
Int J Biol Macromol ; 271(Pt 1): 132614, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38795892

RESUMEN

This study addresses the optimization of the nanolignin preparation method from the areca leaf sheath (ALS) by a mechanical process using a high shear homogenizer at 13,000-16,000 rpm for 1-4 h and its application in enhancing the performance of ultralow molar ratio urea-formaldehyde (UF) adhesive. Response surface methodology (RSM) with a central composite design (CCD) model was used to determine the optimum nanolignin preparation method. The mathematical model obtained was quadratic for the particle size response and linear for the zeta potential response. Under the optimum conditions, a speed of 16,000 rpm for 4 h resulted in a particle size of 227.7 nm and a zeta potential of -18.57 mV with a high desirability value of 0.970. FE-SEM revealed that the characteristic changes of lignin to nanolignin occur from an irregular or nonuniform shape to an oval shape with uniform particles. Nanolignin was introduced during the addition reaction of UF resin synthesis. UF modified with nanolignin (UF-NL) was analyzed for its adhesive characteristics, functional groups, crystallinity, and thermomechanical properties. The UF-NL adhesive had a slightly greater solid content (73.23 %) than the UF adhesive, a gelation time of 4.10 min, and a viscosity of 1066 mPa.s. The UF-NL adhesive had similar functional groups as the UF adhesive, with a lower crystallinity of 59.73 %. Compared with the control plywood which has a tensile shear strength value of 0.79 MPa, the plywood bonded with UF-NL had a greater tensile shear strength of 1.07 MPa, with a lower formaldehyde emission of 0.065 mg/L.


Asunto(s)
Adhesivos , Formaldehído , Urea , Formaldehído/química , Adhesivos/química , Urea/química , Hojas de la Planta/química , Tamaño de la Partícula , Lignina/química
20.
ACS Sens ; 9(5): 2520-2528, 2024 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-38723023

RESUMEN

Alternative energy sources are required due to the decline in fossil fuel resources. Therefore, devices that utilize hydrovoltaic technology and light energy have drawn widespread attention because they are emission-free and solar energy is inexhaustible. However, previous investigations mainly focused on accelerating the water evaporation rate at the electrode interface. Here, a cooperative photoelectrochemical effect on a hydrovoltaic chip is achieved using NH2-MIL-125-modified TiO2 nanotube arrays (NTs). This device demonstrated significantly improved evaporation-triggered electricity generation. Under LED illumination, the open-circuit voltage (VOC) of the NH2-MIL-125/TiO2NTs active layer of the hydrovoltaic chip was enhanced by 90.3% (up to 400.2 mV). Furthermore, the prepared hydrovoltaic chip showed good high-salinity tolerance, maintaining 74.6% of its performance even in 5 M NaCl. By introducing a Schiff-based reaction between the active layer and formaldehyde, a fully integrated flexible sensor was successfully fabricated for formaldehyde monitoring, and a low limit of detection of 5.2 × 10-9 M was achieved. This novel strategy for improving the performance of hydrovoltaic devices offers a completely new general approach to construct self-powered devices for point-of-care sensing.


Asunto(s)
Técnicas Electroquímicas , Formaldehído , Titanio , Formaldehído/análisis , Formaldehído/química , Titanio/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Nanotubos/química , Salinidad , Procesos Fotoquímicos , Electrodos , Límite de Detección
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