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1.
Biosens Bioelectron ; 220: 114892, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36413914

RESUMO

The detection of dopamine in the presence of norepinephrine using nafion-coated boron doped diamond (Nafion-BDD) electrodes was presented. An increase current signal for dopamine could be observed at around 0.75 V using Nafion-BDD, while a change in the current signal of norepinephrine that appears at similar potential was not observed. This might be due to electronegativity of the norepinephrine that is not positive enough to be attracted towards the nafion membrane, albeit neutral enough to pass through the membrane and undergo electrochemical oxidation. An optimization process including accumulation time of dopamine inside the nafion layer, solution of the pH, and nafion thickness was conducted to exploit the difference electrochemical behavior between those two catecholamines at the Nafion-BDD. Using an accumulation time of 300 s, solution pH of 7, and nafion thickness of 1.1 µm, dopamine's LOD was found to be 0.966 µM. Low-interference signal of norepinephrine to the dopamine could be observed with an excellent %recovery of dopamine in 5% range when the concentration of norepinephrine was 10 times lower compared to dopamine concentration.


Assuntos
Técnicas Biossensoriais , Norepinefrina , Dopamina , Boro , Eletrodos
2.
Sci Total Environ ; 858(Pt 2): 159795, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36336040

RESUMO

We synthesized an MFeCoB0.4CNx% (MOF-Fe/Co nanosheets/boron-doped g-C3N4) composite catalyst for enhancing the concurrent photocatalytic-persulfate activation (CPPA) system and achieved efficient degradation of antibiotics. The role of MOF-Fe/Co is to activate persulfate, while boron-doped g-C3N4 can generate photogenerated electrons for the reduction of Co3+/Fe3+ to enhance the regeneration of the active center. The rate constant for Tetracycline degradation by the CPPA system was 4.74 and 7.54 times higher than the photocatalytic and persulfate-activated systems, respectively. This composite was shown to be practical and economically viable for antibiotic degradation. The degradation behavior was explored based on experiments, and molecular orbitals and Fukui functions were obtained by density functional theory calculations. Mechanisms were investigated using reactive oxygen species trapping studies and electron spin resonance, and the process was explained in terms of the charge population and electron density difference of MOF-Fe/Co nanosheets. The CPPA system is an ecologically benign technology for removing antibiotic-related risks to the environment and human health.


Assuntos
Antibacterianos , Boro , Humanos , Luz , Catálise , Tetraciclina
3.
Sci Total Environ ; 858(Pt 1): 159739, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36349634

RESUMO

In these studies of fix boron compounds, associations between tannins and boron (TB) in the form of boric acid appear to be of interest. These TB associations allow the use of boron at very low levels (in compliance with EU restrictions, 2008/58/EC) and limit boron leaching which maintains biological resistance and fire retardant properties. As a consequence, TB wooden products present an extended service life compared to boron compounds alone and were designed to be environmentally-friendly wood protection systems. A follow-up of tannin­boron use identified the environmental impacts using a life cycle assessment (LCA). This LCA was performed on tannin­boron preservative products as well as several industrial preservative-treated timbers and concrete used in the landscape. Cr-containing inorganic salt and an alkaline copper quaternary preservative formulation, as well as concrete, have been used as referential materials to compare the environmental footprint with the tannin­boron treated system. A model was created with life cycle stages used to calculate inputs and outputs during raw material extraction, supplier transportation, manufacturing process, distribution, disposal transportation and processing. Tannin production data were based on Vieira et al. in the field of condensed tannin extraction. However, the extracted tannin in the extraction yield, the inorganic salt, and the process applied are not perfectly comparable with the extraction conditions industrially applied for the Mimosa (Acacia mearnsii) extract which is the major constituent of the TB formulations. The latter is counter-current water extracted without any chemicals or with a limited amount of NaHSO3 or Na2SO3 (at 0.5 % to 1 %) - at a temperature of 70-90 °C. Unfortunately these parameters cannot be elaborated by the LCA program because there is no data available for the production of Na bisulphite or Na bicarbonate in the LCI data used. Other input data were sourced from the ecoinvent v3.8 database. The ReCiPe midpoint method was used to assess the environmental footprint and the CED method was chosen to analyze a general view of the energy-related environmental impacts in the life cycle. Overall, the results demonstrated that tannin­boron preservatives can be regarded as a low-environmental impact formulation. Additionally, an economic analysis of the development of a commercially-viable tannin­boron preservative would now be timely.


Assuntos
Taninos , Madeira , Animais , Madeira/química , Taninos/análise , Taninos/química , Boro/análise , Compostos de Boro/análise , Estágios do Ciclo de Vida
4.
J Colloid Interface Sci ; 632(Pt A): 129-139, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36413939

RESUMO

Stimuli-responsive materials with dynamically switched room-temperature phosphorescence (RTP) aroused great interest. However, the dynamic control of RTP with a color-tunable persistent afterglow by external stimuli is still challenging. Herein, an appealing strategy for constructing dynamic hydrogen-bond networks based on boron-doped carbon quantum dots (BCQDs) was proposed to generate sequence-dependent stimuli-responsive RTP. The BCQDs exhibited bright RTP in paper matrix after successive stimulation by water and heat, demonstrating a fascinating regulation based on an AND logic gate. The RTP generated experienced a reversible switching without attenuation fatigue when BCQDs were heated and exposed to air. The switching of hydrogen-bond network from that among BCQDs to that between BCQDs and paper could facilitate the population of triplet-state BCQDs. The RTP can last a long timie of 10 s after the ceasation of excitation light source. Furthermore, the AND logic gate stimuli-responsive RTP with different colors in papers were obtainded for the first time after blending with various non-RTP dyes. The BCQDs with controllable and on-demand afterglow were further applied for advanced multi-level information encryption and anti-counterfeiting materials. The finding provided assistance to understand the origin and mechanism of the stimuli-responsive RTP of smart materials and offered opportunities for developing multiple continuous stimuli-responsive intelligent RTP materials.


Assuntos
Boro , Pontos Quânticos , Carbono , Temperatura , Hidrogênio
5.
J Hazard Mater ; 442: 130020, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36155296

RESUMO

Exposure to even trace amounts of Cd(II) and Pb(II) in food can have serious effects on the human body. Therefore, the development of novel electrochemical sensors that can accurately detect the different toxicity levels of heavy metal ions in food is of great significance. Based on the principle of green chemistry, we propose a new type of boron and nitrogen co-doped carbon (BCN) material derived from a metal-organic framework material and study its synthesis, characterization, and heavy-metal ion detection ability. Under the optimum conditions, the BCN-modified glassy carbon electrode was studied using square-wave anodic stripping voltammetry, which showed good electrochemical responses to Cd(II) and Pb(II), with sensitivities as low as 0.459 and 0.509 µA/µM cm2, respectively. The sensor was successfully used to detect Cd(II) and Pb(II) in Beta vulgaris var. cicla L samples, which is consistent with the results obtained using inductively coupled plasma-mass spectrometry. It also has a strong selectivity for complex samples. This study provides a novel approach for the detection of heavy metal ions in food and greatly expands the application of heteroatom-doped metal-free carbon materials in detection platforms.


Assuntos
Estruturas Metalorgânicas , Metais Pesados , Oligoelementos , Humanos , Carbono/química , Boro , Nitrogênio , Cádmio/química , Porosidade , Chumbo , Metais Pesados/análise
6.
Environ Res ; 216(Pt 1): 114454, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36228687

RESUMO

In this study, the use of boron-based materials on efficiency of environmentally friendly porous ceramics was investigated. In this context, a glaze formulation was created that uses high amounts of frit and sintered at low temperatures. Boric acid and colemanite were added to glaze formulations and different alternative formulations were created by reducing the frit percentage. These materials were added to these glaze formulations in two different ways, calcined and raw. The glaze mixtures obtained from the formulations were applied on the ceramic body and fired at 950-1000-1020-1100-1200 °C in the laboratory oven. Crystal phase structures of glaze samples containing boric acid and colemanite were analyzed by X-Ray Crystallography (XRD) method. The surface properties and characterizations of the obtained samples were examined by scanning electron microscopy (SEM). Differential Thermal Analysis and Thermogravimetric analysis (DTA/TG) were performed to determine their thermal behavior and mass loss. As a result of the analysis, it was observed that boron derivatives are a good flux agent and do not have a negative effect on the surface and other technical properties of the glaze. In the formulations of glazes with high frit content and processed at low temperatures, the percentage of frit has been reduced and costs have been improved. Also, energy costs were improved with the reduction in firing temperatures. Considering the energy and raw material costs of this study, it is predicted that high efficiency will be achieved in the process.


Assuntos
Boro , Cerâmica , Porosidade , Propriedades de Superfície
7.
J Hazard Mater ; 442: 130016, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36179625

RESUMO

To address the difficulty of precisely regulating the two-electron oxygen reduction reaction (2e-ORR) and investigate the synergistic effect of hydrogen peroxide (H2O2) and peroxymonosulfate (PMS), a heterogeneous electro-catalyst was synthesized via carbonation of boron (B) and sulfur (S) co-doping electrospun nanofibers containing iron and cobalt (B, S-Fe/Co@C-NCNFs-900), and used to degrade levofloxacin (Levo) in the electro-activating PMS with self-made cathode material (E-cathode-PMS) system. The morphological, structural, and electrochemical characteristics have been investigated. The results showed that B and S co-doping could remarkably enhance electron transfer and manage two-electron oxygen reduction, which was more favorable for H2O2 generation. Levo degradation efficiency could reach 99.63% with a reaction rate of 0.3056 min-1 in 20 min under the appropriate conditions (pH = 4, current = 20 mA, and [PMS] = 8.0 mM). The steady-state concentration of singlet oxygen (1O2) was calculated to be 669.17 × 10-14 M, which was 15.42, 29.74, and 45.00 times respectively than that of HO2·/O2·- (43.40 × 10-14 M), ·OH (22.25 × 10-14 M) and SO4-·(14.87 × 10-14 M), signifying that 1O2 was the predominant reactive oxygen species (ROS) involved in Levo removal. The high TOC removal (74.19%), low energy consumption (0.14 kWh m-3 order-1), few intermediates toxicity, and excellent Levo degradation efficiency for complex wastewater with various anions and matrixes showed the prospective practical applications of the E-cathode-PMS system. Overall, this study provides a useful strategy to regulate and control the 2e-ORR pathway.


Assuntos
Nanofibras , Poluentes Químicos da Água , Carbono/química , Peróxido de Hidrogênio/química , Levofloxacino , Águas Residuárias , Boro , Espécies Reativas de Oxigênio , Oxigênio Singlete , Estudos Prospectivos , Poluentes Químicos da Água/química , Oxirredução , Peróxidos/química , Eletrodos , Ferro/química , Enxofre , Cobalto , Oxigênio
8.
J Colloid Interface Sci ; 629(Pt A): 813-821, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36108552

RESUMO

Flexible fiber-shaped supercapacitors (FSSCs) are promising candidates as electrode materials for the development of deformable electronic devices. Although tremendous efforts have been focused on the preparation of flexible electrode materials, traditional FSSCs materials face problems of inferior stability and complicated processes. Boron-doped diamond (BDD) holds promise as a FSSC electrode, owing to its well-established preparation process, strong acid and alkali corrosion resistance, environmentally and skin-friendly characteristics. Here, we reported a novel strategy for the construction of BDD-based FSSCs by growing a BDD film on a flexible tantalum (Ta) fiber substrate through hot filament chemical vapor deposition technique. Results showed that the BDD fiber film featured 10 folds improvement in specific capacitance than a planar BDD electrode. A symmetric supercapacitor device was assembled using the BDD fiber electrode and achieved an energy density of 25.6 mJ cm-2 at a power density of 0.6 mW cm-2, and a desirable stability with higher capacitance retention of 93.5% after 20,000 cycles. Furthermore, the symmetric BDD fiber device exhibited satisfactory bendability with high specific capacitance retention under various bending deformations. The findings in this research work hold promise for the fabrication of high performance flexible FSSCs.


Assuntos
Boro , Diamante , Tantálio , Eletrodos , Álcalis
9.
Talanta ; 252: 123778, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35998443

RESUMO

Detecting proteins via surface assisted laser desorption/ionization mass spectrometry (SALDI-MS) method is still highly challenging, and only few examples of nanomaterials have been demonstrated to perform such detection so far. In this study, carbon nanowalls (CNWs), vertically aligned graphene sheet-based materials, presenting specific morphology, dimensions, and boron doping levels have shown improved performances for both qualitative and quantitative detection of Cytochrome C under optimized experimental conditions. Boron doped carbon nanowalls (B-CNWs) with a [B]/[C] ratio of 5000 ppm and growing time of 4 h have shown the best performance in terms of signal intensity and reliability. Then, the detection of ricin, a ribosomal-inhibiting protein (RIP) classified as category B bioterrorism agent by CDC (Centre of Disease and Control and Prevention), was performed. For the first time, direct SALDI-MS detection of ricin B chain was reported without tedious sample preparation steps or database interrogation, and results were obtained within few minutes and a limit of detection (LOD) of 0.5 pmol/µl was obtained. Thanks to the introduction of galactosamine residues on B-CNW, we were able to selectively detect ricin B chain protein in complex media such as serum and soft drinks with enhanced signal intensity. B-CNWs are not toxic and are adaptable to any commercial MALDI-TOF mass spectrometer, showing their great potential as SALDI based materials.


Assuntos
Carbono , Ricina , Carbono/química , Boro , Citocromos c , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Reprodutibilidade dos Testes , Lasers
10.
J Inorg Biochem ; 238: 112027, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36345068

RESUMO

Boron-containing compounds (BCC) exert effects on neurons. After the expanding of both the identification and synthesis of new BCC, novel effects in living systems have been reported, many of these involving neuronal action. In this review, the actions of BCC on neurons are described; the effects have been inferred by boron deprivation or addition. Also, the effects can be related to those mediated by interaction on ionic channels, G-protein coupled receptors, or other receptors exerting modification on neuronal behavior. Additionally, BCC have exhibited effects by the modulation of inflammation or oxidative processes. BCC are expanding as drugs. Deprivation of boron sources from the diet shows the role of some natural BCC. However, the observations of several new synthesized compounds suggest their ability to act with attractive potency, efficacy, and long-term action on neuronal receptors or processes related with the origin and evolution of neurodegenerative processes. The details of BCC-target interactions are currently being elucidated in progress, as those observed from BCC-protein crystal complexes. Taking all of the above into account, the expansion is presumably near to having studies on the application of BCC as drugs on specific targets for treating neurodegenerative diseases.


Assuntos
Doenças Neurodegenerativas , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Boro , Compostos de Boro/química , Neurônios , Inflamação
11.
Nat Commun ; 13(1): 7353, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36446788

RESUMO

Bacteria and excessive inflammation are two main factors causing non-healing wounds. However, current studies have mainly focused on the inhibition of bacteria survival for wound healing while ignoring the excessive inflammation induced by dead bacteria-released lipopolysaccharide (LPS) or peptidoglycan (PGN). Herein, a boron-trapping strategy has been proposed to prevent both infection and excessive inflammation by synthesizing a class of reactive metal boride nanoparticles (MB NPs). Our results show that the MB NPs are gradually hydrolyzed to generate boron dihydroxy groups and metal cations while generating a local alkaline microenvironment. This microenvironment greatly enhances boron dihydroxy groups to trap LPS or PGN through an esterification reaction, which not only enhances metal cation-induced bacterial death but also inhibits dead bacteria-induced excessive inflammation both in vitro and in vivo, finally accelerating wound healing. Taken together, this boron-trapping strategy provides an approach to the treatment of bacterial infection and the accompanying inflammation.


Assuntos
Nanopartículas Metálicas , Infecção dos Ferimentos , Humanos , Peptidoglicano , Lipopolissacarídeos/toxicidade , Boro/farmacologia , Cicatrização , Bactérias , Ligante de CD40 , Inflamação , Compostos de Boro
12.
Water Res ; 227: 119323, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36395565

RESUMO

Nowadays metal-free persulfate-based advanced oxidation processes (AOPs) have been intensively investigated, however, the catalysts are often too complex to fully consider their application potential. Conventional AOPs usually suffer from severe interference in real water matrix, thus, selective oxidation is practically and scientifically challenging as it could avoid unnecessary inputs of energy and possible secondary pollutants. In this study, a remarkably synergistic effect was achieved when conventional amorphous boron/peroxymonosulfate (Boron/PMS, 0.67 × 10-2 min-1) system was combined with electrolysis (E-Boron/PMS, 1.54 × 10-2 min-1) to degrade sulfamethoxazole (SMX). Evidenced by selectively quenching tests with kinetic evaluation, electron paramagnetic resonance (EPR), solvent-exchange experiment and electrochemical analysis, the dominated reactive oxygen species in E-Boron/PMS system tended to be 1O2, instead of the •OH and SO4•-. Mechanistic study unveiled that 1O2 was generated via accelerated PMS self-decomposition, triggered by interface alkalization and hydroxyl radicals transfer at the cathode interface. 1O2 is considered to be selective to the electron-rich organic compounds, thus E-Boron/PMS system was superior to conventional radical-dominated system (Boron/PMS) for SMX removal in the co-presence of common inorganic anions, showing the great merits of selective oxidation in nonradical system. These findings provided new insights into effective and selective oxidation of SMX via E-Boron/PMS system, which shed new light on the development of nonradical system.


Assuntos
Boro , Peróxidos , Peróxidos/química , Metais , Oxirredução , Sulfametoxazol
13.
Ecotoxicol Environ Saf ; 248: 114295, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36402074

RESUMO

This sugar beet acts as a soil remediator in areas where there are high levels of boron (B) in the soil, since it has a high requirement of boron (B) for growth, and has strong resistance to high B levels. Although B toxicity in different plants has been widely researched, little is known about the response of photosystem II (PSII) activity in sugar beet leaves to B toxicity at present. To clarify the growth and photosynthetic physiological response of sugar beet to B toxicity, the effects of different concentrations of H3BO3 (0.05, 1.5, 2.5,3.5 mM) on the growth, photosynthetic characteristics and antioxidant defense system of sugar beet seedlings were investigated by hydroponic experiments. In the present study, high B stress inhibited the growth of sugar beet and significantly decreased the biomass of the plants. There was a remarkable increase in the accumulation of B in the shoots, which affected photosynthesis and decreased the photosynthetic pigments. As B toxicity increased, leaf PSII activities and maximum photochemical efficiency of PSII (Fv/Fm) showed a tendency to decrease; at the same time, the photosynthetic performance index based on absorbed light energy (PIABS) decreased as well. Meanwhile, the energy allocation parameters of the PSII reaction center were changed, the light energy utilization capacity and the energy used for electron transfer were reduced and the thermal dissipation was increased at the same time. Furthermore, B toxicity decreased catalase (CAT) activity, increased peroxidase (POD) and superoxide dismutase (SOD) activities, and increased malondialdehyde (MDA) accumulation. According to the results obtained in this study, high B concentrations reduced the rate of photosynthesis and fluorescence, thus weakened antioxidant defense systems, and therefore inhibited the growth of sugar beet plants. Thus, in high B areas, sugar beet possesses excellent tolerance to high B levels and has a high B translocation capacity, so it can be used as a phytoremediation tool. This study provides a basis for the feasibility of sugar beet resistant to high B environments.


Assuntos
Beta vulgaris , Complexo de Proteína do Fotossistema II , Boro/toxicidade , Antioxidantes , Verduras , Solo , Açúcares
14.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36430206

RESUMO

The design of highly selective low-toxic, low-molecular weight agents for boron delivery to tumour cells is of decisive importance for the development of boron neutron capture therapy (BNCT), a modern efficient combined method for cancer treatment. In this work, we developed a simple method for the preparation of new closo- and nido-carborane-containing folic acid bis-amides containing 18-20 boron atoms per molecule. Folic acid derivatives containing nido-carborane residues were characterised by high water solubility, low cytotoxicity, and demonstrated a good ability to deliver boron to tumour cells in in vitro experiments (up to 7.0 µg B/106 cells in the case of U87 MG human glioblastoma cells). The results obtained demonstrate the high potential of folic acid-nido-carborane conjugates as boron delivery agents to tumour cells for application in BNCT.


Assuntos
Boro , Glioblastoma , Humanos , Boro/farmacologia , Amidas , Ácido Fólico/farmacologia , Magreza
15.
Int J Mol Sci ; 23(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36430949

RESUMO

Organic nanomaterials have attracted considerable attention in the area of photodynamic and photothermal therapy, owing to their outstanding biocompatibility, potential biodegradability, well-defined chemical structure, and easy functionalization. However, it is still a challenge to develop a single organic molecule that obtains both photothermal and photodynamic effects. In this contribution, we synthesized a new boron-dipyrromethene (BODIPY)-based derivative (DPBDP) with an acceptor-donor-acceptor (A-D-A) structure by coupling 3,6-di(2-thienyl)-2,5-dihydropyrrolo [3,4-c] pyrrole-1,4-dione (DPP) and BODIPY. To enhance the hydrophilicity of the BODIPY derivative, the polyethylene glycol (PEG) chains were introduced to the meso- position of BODIPY core. The amphiphilic DPBDP was then self-assembled into related nanoparticles (DPBDP NPs) with improved hydrophilicity and enhanced absorbance in the NIR region. DPBDP NPs could simultaneously generate the singlet oxygen (1O2) and heat under the irradiation of a single laser (690 nm). The 1O2 quantum yield and photothermal conversion efficiency (PCE) of DPBDP NPs were calculated to be 14.2% and 26.1%, respectively. The biocompatibility and phototherapeutic effect of DPBDP NPs were evaluated through cell counting kit-8 (CCK-8) assay. Under irradiation of 690 nm laser (1.0 W/cm2), the half maximal inhibitory concentration (IC50) of DPBDP NPs was calculated to be 16.47 µg/mL. Thus, the as-prepared DPBDP NPs could be acted as excellent candidates for synergistic photodynamic/photothermal therapy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Boro , Células HeLa , Nanopartículas/química , Neoplasias/tratamento farmacológico
16.
Molecules ; 27(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36432012

RESUMO

A boron-dipyrromethene (BODIPY) derivative reactive towards amino groups of proteins (NHS-Ph-BODIPY) was synthesized. Spectroscopic and photophysical properties of amine-reactive NHS-Ph-BODIPY and its non-reactive precursor (COOH-Ph-BODIPY) in a number of organic solvents were investigated. Both fluorescent dyes were characterized by green absorption (521-532 nm) and fluorescence (538-552 nm) and medium molar absorption coefficients (46,500-118,500 M-1·cm-1) and fluorescence quantum yields (0.32 - 0.73). Solvent polarizability and dipolarity were found to play a crucial role in solvent effects on COOH-Ph-BODIPY and NHS-Ph-BODIPY absorption and emission bands maxima. Quantum-chemical calculations were used to show why solvent polarizability and dipolarity are important as well as to understand how the nature of the substituent affects spectroscopic properties of the fluorescent dyes. NHS-Ph-BODIPY was used for fluorescent labeling of a number of proteins. Conjugation of NHS-Ph-BODIPY with bovine serum albumin (BSA) resulted in bathochromic shifts of absorption and emission bands and noticeable fluorescence quenching (about 1.5 times). It was demonstrated that the sensitivity of BSA detection with NHS-Ph-BODIPY was up to eight times higher than with Coomassie brilliant blue while the sensitivity of PII-like protein PotN (PotN) detection with NHS-Ph-BODIPY and Coomassie brilliant blue was almost the same. On the basis of the molecular docking results, the most probable binding sites of NHS-Ph-BODIPY in BSA and PotN and the corresponding binding free energies were estimated.


Assuntos
Boro , Corantes Fluorescentes , Corantes Fluorescentes/química , Aminas , Simulação de Acoplamento Molecular , Solventes/química , Soroalbumina Bovina
17.
Molecules ; 27(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36432171

RESUMO

In the presented study, the effects of ROCK inhibitor Y-27632, antifreeze protein III, and boron at two different doses were investigated on the spermatological parameters of Ankara buck semen after freeze-thawing. Ejaculates were collected from bucks using an electroejaculator during the breeding season. The ejaculates that showed appropriate characteristics were pooled and used in the dilution and freezing of semen. The extender groups were formed by adding two different doses of three different additives (ROCK inhibitor Y-27632, 5 and 20 µM; antifreeze protein III, 1 and 4 µg/mL; boron, 0.25 and 1 mM) to the control extender. The semen was diluted with the different extenders at 35-37 °C and loaded into straws. Sperm samples frozen in liquid nitrogen vapors, following equilibration, were stored in liquid nitrogen. It was observed that extender supplementation improved post-thaw motility of Ankara buck semen after freeze-thawing. Differences were significant (p < 0.01) for 5 and 10 µM doses of ROCK inhibitor (71.82% and 74.04 % motility), as well as for 0.25 and 1 mM doses of boron (76.36% and 72.08% motility), compared to the control group (66.15% motility). With respect to the evaluation of acrosomal integrity and mitochondrial activity after freeze-thawing, although supplementation provided protection at all doses, the efficacy was not statistically significant (p > 0.05). It was observed that DNA damage was improved by antifreeze protein III at 1 µg/mL (1.23% ± 0.23%) and by boron at all doses (0.25 mM: 1.83% and 1 mM: 1.18%) compared to the control group (3.37%) (p < 0.01), following the thawing process. In the present study, it was determined that some additives added to the extender provided significant improvements in buck spermatozoa motility and DNA damage after thawing.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Humanos , Preservação do Sêmen/métodos , Boro/farmacologia , Boro/metabolismo , Quinases Associadas a rho/metabolismo , Criopreservação/métodos , Crioprotetores/farmacologia , Proteínas Anticongelantes/metabolismo , Nitrogênio/metabolismo
18.
Molecules ; 27(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36364299

RESUMO

In an attempt to isolate boron-containing tri-niobium polychalcogenide species, we have carried out prolonged thermolysis reactions of [Cp*NbCl4] (Cp* = ɳ5-C5Me5) with four equivalents of Li[BH2E3] (E = Se or S). In the case of the heavier chalcogen (Se), the reaction led to the isolation of the tri-niobium cubane-like cluster [(NbCp*)3(µ3-Se)3(BH)(µ-Se)3] (1) and the homocubane-like cluster [(NbCp*)3(µ3-Se)3(µ-Se)3(BH)(µ-Se)] (2). Interestingly, the tri-niobium framework of 1 stabilizes a selenaborate {Se3BH}- ligand. A selenium atom is further introduced between boron and one of the selenium atoms of 1 to yield cluster 2. On the other hand, the reaction with the sulfur-containing borate adduct [LiBH2S3] afforded the trimetallic clusters [(NbCp*)3(µ-S)4{µ-S2(BH)}] (3) and [(NbCp*)3(µ-S)4{µ-S2(S)}] (4). Both clusters 3 and 4 have an Nb3S6 core, which further stabilizes {BH} and mono-sulfur units, respectively, through bi-chalcogen coordination. All of these species were characterized by 11B{1H}, 1H, and 13C{1H} NMR spectroscopy, mass spectrometry, infrared (IR) spectroscopy, and single-crystal X-ray crystallography. Moreover, theoretical investigations revealed that the triangular Nb3 framework is aromatic in nature and plays a vital role in the stabilization of the borate, borane, and chalcogen units.


Assuntos
Compostos Organometálicos , Selênio , Boratos , Compostos Organometálicos/química , Modelos Moleculares , Nióbio , Boro , Enxofre/química
19.
Environ Monit Assess ; 195(1): 110, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36378353

RESUMO

The aim of this study was to investigate the accumulation of boron (B) in the soils, sediments, and plants in the wastewater (treated and untreated) irrigation farmlands. Twelve sites of soils and four sites of sediments were collected in two wastewater irrigation areas of Tianjin, China. Our results show that the long-term irrigation of wastewater induced B accumulation in the soils (81 - 90 mg kg-1 on average) and sediments (112 - 150 mg kg-1 on average). The readily available B fractions, salt extractable B and water extractable B, accounted for more than half of the extractable B. The plant available B in the soils exceeded toxic levels of most sensitive crops but B in plant leaves did not reach the thresholds. This study indicates that long-term irrigation of wastewater would induce excess accumulation of B in the soils of the farmlands and might pose a toxicity risk to the plants.


Assuntos
Poluentes do Solo , Águas Residuárias , Solo , Boro , Poluentes do Solo/análise , Monitoramento Ambiental , Produtos Agrícolas , China , Irrigação Agrícola
20.
J Am Chem Soc ; 144(43): 19953-19972, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36269121

RESUMO

The total syntheses of aflastatin A and its C3-C48 degradation fragment (6a, R = H) have been accomplished. The syntheses feature several complex diastereoselective fragment couplings, including a Felkin-selective trityl-catalyzed Mukaiyama aldol reaction, a chelate-controlled aldol reaction involving soft enolization with magnesium, and an anti-Felkin-selective boron-mediated oxygenated aldol reaction. Careful comparison of the spectroscopic data for the synthetic C3-C48 degradation fragment to that reported by the isolation group revealed a structural misassignment in the lactol region of the naturally derived degradation product. Ultimately, the data reported for the naturally derived aflastatin A C3-C48 degradation lactol (6a, R = H) were attributed to its derivative lactol trideuteriomethyl ether (6c, R = CD3). Additionally, the revised absolute configurations of six stereogenic centers (C8, C9, and C28-C31) were confirmed.


Assuntos
Aldeídos , Pirrolidinonas , Boro , Estereoisomerismo , Estrutura Molecular
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