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1.
J Hazard Mater ; 422: 126939, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34449342

RESUMO

Sodium tetraborate pentahydrate (STB) was intercalated into graphene oxide (GO) nanosheets to form a nanocomposite (STB@GO). Subsequently, it was self-assembled on a substrate membrane to prepare STB@GO nanofiltration membrane. The properties of the STB@GO powder samples and the nanofiltration membrane were studied using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), contact angle (CA), and zeta potential. When the STB concentration was 1.0 g/L in the cross-linking reaction, the membrane was described as the STB2@GO membrane and exhibited a large interlayer space (d-spacing = 1.347 nm), high hydrophilicity (CA = 22.2°), and high negative potential (zeta = -18.0 mV). Meanwhile, the pure water flux of the membrane was significantly increased by 56.60% than that of the GO membrane. In addition, the STB2@GO membrane exhibited a favorable capability for dye rejection,98.52% for Evans blue (EB), 99.26% for Victoria blue B (VB), 91.94% for Alizarin yellow (AY), and 93.21% for Neutral red (NR). Furthermore, the STB2@GO membrane performed better in dye separation under various types and concentrations of dye, pH values, and ions in solution. Thus, this study provides a promising method for preparing laminated GO nanofiltration membranes for dye wastewater treatment.


Assuntos
Grafite , Purificação da Água , Boratos
2.
Sci Total Environ ; 803: 149902, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34482144

RESUMO

Nitrogen (N) use efficiency can be increased by the addition of substances to urea. Magnesium sulfate (MgSO4) and boron were considered as plant nutrients, while zeolite was used as soil conditioner. The addition of these substances may affect soil NH3 and N2O emissions, by increasing N use efficiency. We conducted an 30 days incubation experiment with ryegrass using fertilizer treatments (12 g N m-2) as follows: urea (U); urea + MgSO4 (UM); urea + MgSO4 + borax (UMB); zeolite + urea + MgSO4 (Z-UM); and zeolite + urea + MgSO4 + borax (Z-UMB). We measured NH3 and N2O emissions and the aboveground N uptake of ryegrass. Cumulative NH3 emissions of UM, UMB, Z-UM and Z-UMB were 10%, 53%, 21% and 58% lower than U, respectively, while their N2O emissions were 32%, 133%, 43% and 72% higher than U, respectively. Aboveground N uptake of UM, UMB, Z-UM and Z-UMB were 9%, 6%, 12% and 13% higher than U, respectively. Overall, we suggest that the addition of MgSO4 and borax were effective in reducing NH3 emissions and potentially increase plant N uptake. However, the risk of higher denitrification and N2O emissions also needs to be considered. This study reveals the considerable effect of MgSO4 and borax in soil N cycles. Future research should evaluate how the application of urea + MgSO4 + borax effects gaseous emissions and crop yield of dicotyledons and in drier soil conditions.


Assuntos
Solo , Ureia , Agricultura , Boratos , Fertilizantes/análise , Sulfato de Magnésio , Nitrogênio/análise , Óxido Nitroso/análise , Poaceae
3.
Biol Trace Elem Res ; 200(1): 197-205, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33559025

RESUMO

The widespread industrial use of nitrite in preservatives, colorants, and manufacturing rubber products and dyes increases the possibilities of organ toxicity. Lithium borate (LB) is known as an antioxidant and an oxidative stress reliever. Therefore, this study is aimed at examining the effect of LB on nitrite-induced hepatorenal dysfunction. Twenty-eight male Swiss mice were divided into four equal groups. Group 1, the control group, received saline. Group 2 received LB orally for 5 consecutive days at a dose of 15 mg/kg bw. Group 3, the nitrite group, received sodium nitrite (NaNO2) on Day 5 (60 mg/kg bw intraperitoneally). Group 4, the protective group (LB + NaNO2 group), received LB for 5 days and then a single dose of NaNO2 intraperitoneally on Day 5, the same as in Groups 2 and 3, respectively. Samples of blood and kidney were taken for serum analysis of hepatorenal biomarkers, levels of antioxidants and cytokines, and the expression of genes associated with oxidative stress and inflammation. NaNO2 intoxication increased markers of liver and kidney functions yet decreased reduced glutathione (GSH), superoxide dismutase (SOD), and catalase activities in blood. NaNO2 also increased the expression of tumor necrosis factor (TNF-α), interleukin-1ß and interleukin-6 (IL-1ß and IL-6). Pre-administration of LB protected mice from oxidative stress, lipid peroxidation, and the decrease in antioxidant enzyme activity. Moreover, LB protected mice from cytokine changes, which remained within normal levels. LB ameliorated the changes induced by NaNO2 on the mRNA of nuclear factor erythroid 2-related factor 2 (Nfr2), heme oxygenase-1 (HO-1), nuclear factor-kappa B (NF-κB), transforming growth factor-beta 2 (TGF-ß2), and glutathione-S-transferase (GST) as determined using quantitative real-time PCR (qRT-PCR). These results collectively demonstrate that LB ameliorated NaNO2-induced oxidative stress by controlling the oxidative stress biomarkers and the oxidant/antioxidant state through the involvement of the Nrf2/HO-1 and NF-κB signaling pathways.


Assuntos
Heme Oxigenase-1 , Fator 2 Relacionado a NF-E2 , Animais , Antioxidantes/farmacologia , Boratos/farmacologia , Heme Oxigenase-1/metabolismo , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Oxidantes , Estresse Oxidativo , Nitrito de Sódio/toxicidade
4.
Acta Cir Bras ; 36(11): e361105, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34909839

RESUMO

PURPOSE: The development of cutting surface leakage and postoperative peritoneal adhesions (PPA) after sleeve gastrectomy (SG) are the most serious operative complications. We investigated the effectiveness of the newly developed glycerol and sodium pentaborate containing formulation on the prevention of these complications. METHODS: Sixteen Sprague Dawley rats (mean weight 310 ± 50 g, mean age 3 months old) were divided into two groups, consisting of eight rats in each. SG and a double-layer suture technique were performed for each group. In study group, there was the mixture of 2 mL 3% glycerol plus 3% sodium pentaborate formulation, and in the control group 2 mL 0.9% NaCl was injected into the peritoneal cavity. Rats were sacrificed after 30 days, then macroscopic adhesion grade scoring and histopathological evaluations were assessed. RESULTS: Macroscopic PPA scores in the control and study groups were 2.75 ± 0.16 and 1.50 ± 0.327, respectively (p = 0.004). Histopatologic fibrosis scores in the control and study groups were 0.87 ± 0.125 and 2.00 ± 0.26, respectively (p = 0.002). CONCLUSIONS: In SG operation model, glycerol plus sodium pentaborate compound decreased PPA formation and also increased stomach cut surface line fibrosis. This new formulation is hopeful for more safe SG operations.


Assuntos
Gastrectomia , Glicerol , Animais , Boratos , Ratos , Ratos Sprague-Dawley , Aderências Teciduais/prevenção & controle
5.
Huan Jing Ke Xue ; 42(10): 4789-4797, 2021 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-34581121

RESUMO

Peroxymonosulfate(PMS)-based advanced oxidation processes were widely used for the degradation of organic pollutants. Electron-rich azo dye Acid Orange 7(AO7) was selected as the target organic matter in this work. The differences, influencing factors, efficiency, and mechanisms of a PMS/Co2+ homogeneous system in the degradation of organic pollutants with two different buffers of boric acid(Lewis acid) and phosphoric acid(Bronstede acid) were investigated. The k value of AO7 degradation in the PMS/Co2+ homogeneous system with phosphate buffer was greater than that with borate buffer, but the degradation percentage during the first 10 seconds of the reaction was lower in the former case. These differences were affected by buffer concentration, the PMS and Co2+ dosages, and pH. In the phosphate buffer, ·OH or SO4-· contributed to organic degradation in the PMS/Co2+ system, while in the borate buffer, the nonradical pathway(1O2) made a critical contribution to the removal of organics. This study provides a reference for the application of different types of buffers in the homogeneous catalysis of PMS.


Assuntos
Boratos , Poluentes Ambientais , Catálise , Oxirredução , Peróxidos , Fosfatos
6.
Environ Sci Technol ; 55(18): 12724-12730, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34473928

RESUMO

The role of boron in terrestrial plant physiology is diverse and increasingly well understood, but its role in marine aquatic eukaryotes is less clear. Our research reveals a distinctive and large offset in boron isotopes from seawater, irrespective of seaweed type or season. We show that the offset is consistent with the incorporation of borate from seawater. Boron is a known micronutrient in plants but very few studies have used boron isotopes to investigate boron's role in plant physiology. Seaweed, as the most primitive multicellular plant, has an important role in investigating wider plant adaptations that use boron to meet functional needs. Furthermore, seaweed and other plants are a key base nutrient provider in food webs, supplying boron to consumers and playing a critical role in boron environmental cycling.


Assuntos
Boratos , Alga Marinha , Boro , Isótopos , Plantas
7.
Anal Chim Acta ; 1176: 338769, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34399896

RESUMO

A novel magnetic borate-modified MXene composite was prepared by in situ growth of Fe3O4 particles onto the surface of phenylboronic acid modified Ti3C2Tx nanosheets. The magnetic composite possesses highly selective recognition properties to catecholamines, and high adsorption capacity (up to 319.6 µmol g-1) for dopamine. Besides, the adsorption of urinary catecholamines can be accomplished within 2.0 min. The excellent adsorption performance can be assigned to its unique 2D layered structures, which helps to shorten the diffusion path and facilitate molecular transport. In addition, the multilayer adsorption and the synergetic interactions of borate affinity, van der Waals forces, hydrogen bonding and π-π stacking also contribute to the adsorption. By coupling the magnetic boronate affinity composites with high-performance liquid chromatography-fluorescence detection, a sensitive method for the determination of catecholamines in urine samples was proposed. The validation results revealed it can offer good linearities (correlation coefficients higher than 99%). The method detection limits were 0.06, 0.16, 0.03 and 0.14 ng mL-1 for norepinephrine, epinephrine, dopamine and isoprenaline, respectively, and relative recoveries for these catecholamines were in the range of 98.56-108.1%, 92.56-110.0%, 98.79-112.3% and 88.14-97.81%, respectively. The proposed method was successfully applied to analyze the catecholamines in the urine samples from 15 healthy volunteers and 16 patients with Alzheimer's disease. The results indicated that the magnetic borate-modified Mxene composite possesses superior extraction performance, and can be used as an outstanding candidate for the extraction of catecholamines in pre-clinical or clinical studies.


Assuntos
Boratos , Catecolaminas , Adsorção , Cromatografia Líquida de Alta Pressão , Humanos , Fenômenos Magnéticos , Magnetismo , Extração em Fase Sólida
8.
ACS Appl Mater Interfaces ; 13(33): 40013-40031, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34375080

RESUMO

Flexible and wearable hydrogel strain sensors have attracted tremendous attention for applications in human motion and physiological signal monitoring. However, it is still a great challenge to develop a hydrogel strain sensor with certain mechanical properties and tensile deformation capabilities, which can be in conformal contact with the target organ and also have self-healing properties, self-adhesive capability, biocompatibility, antibacterial properties, high strain sensitivity, and stable electrical performance. In this paper, an ionic conductive hydrogel (named PBST) is rationally designed by proportionally mixing polyvinyl alcohol (PVA), borax, silk fibroin (SF), and tannic acid (TA). SF can not only be a reinforcement to introduce an energy dissipation mechanism into the dynamically cross-linked hydrogel network to stabilize the non-Newtonian behavior of PVA and borax but it can also act as a cross-linking agent to combine with TA to reduce the dissociation of TA on the hydrogel network, improving the mechanical properties and viscoelasticity of the hydrogel. The combination of SF and TA can improve the self-healing ability of the hydrogel and realize the adjustable viscoelasticity of the hydrogel without sacrificing other properties. The obtained hydrogel has excellent stretchability (strain > 1000%) and shows good conformal contact with human skin. When the hydrogel is damaged by external strain, it can rapidly self-repair (mechanical and electrical properties) without external stimuli. It shows adhesiveness and repeatable adhesiveness to different materials (steel, wood, PTFE, glass, iron, and cotton fabric) and biological tissues (pigskin) and is easy to peel off without residue. The obtained PBST conductive hydrogel also has a wide strain-sensing range (>650%) and reliable stability. The hydrogel adhered to the skin surface can monitor large strain movements such as in finger joints, wrist joints, knee joints, and so on and detect swallowing, smiling, facial bulging and calming, and other micro-deformation behaviors. It can also distinguish physical signals such as light smile, big laugh, fast and slow breathing, and deep and shallow breathing. Therefore, the PBST conductive hydrogel material with multiple synergistic functions has great potential as a flexible wearable strain sensor. The PBST hydrogel has antibacterial properties and good biocompatibility at the same time, which provides a safety guarantee for it as a flexible wearable strain sensor. This work is expected to provide a new way for people to develop ideal wearable strain sensors.


Assuntos
Adesivos/química , Materiais Biocompatíveis/química , Fibroínas/química , Hidrogéis/química , Substâncias Viscoelásticas/química , Animais , Antibacterianos/química , Materiais Biocompatíveis/metabolismo , Boratos/química , Sobrevivência Celular/efeitos dos fármacos , Reagentes para Ligações Cruzadas/química , Condutividade Elétrica , Técnicas Eletroquímicas , Desenho de Equipamento/instrumentação , Desenho de Equipamento/métodos , Fibroblastos/citologia , Humanos , Hidrogéis/metabolismo , Camundongos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Movimento , Álcool de Polivinil/química , Reologia , Pele , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície , Taninos/química , Dispositivos Eletrônicos Vestíveis , Cicatrização
9.
Luminescence ; 36(7): 1706-1715, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34159716

RESUMO

Neodymium-doped glass finds application in lasers with high energy and low pulse width. In the present study, a series of Nd3+ ions (0-2 mol%)-doped strontium borophosphate (SBP) glass samples was prepared through the conventional melt quench method. A broad peak in the X-ray diffraction spectrum confirmed the formation of a single-phase amorphous borophosphate glass. Fourier transform infrared spectra of the doped and undoped glass samples indicated the presence of borate and phosphate groups that form the anionic network. The thermal properties of the glass samples were determined from thermogravimetry/differential thermal analysis. Photoluminescence and ultraviolet-visible light techniques were used to investigate the optical properties of the as-prepared SBP:Nd glass. The Judd-Ofelt (JO) intensity parameters Ωλ (2, 4, 6), stimulated emission cross-section, branching ratios, and transition probabilities of the Nd3+ -doped glass were obtained through the JO analysis. Characteristic Nd3+ emission peaks were observed at 1330, 1060, and 876 nm, corresponding to the 4 F3/2 →4 IS/2 (S = 13, 11, and 9) transitions, respectively. The suitability of SBP:Nd (0.5 mol%) glass for use in solid-state lasers was demonstrated by its intense luminescence, high transition probability, high emission cross-section, optical gain, and luminescence branching ratio.


Assuntos
Neodímio , Estrôncio , Boratos , Vidro , Luminescência
10.
Sci Rep ; 11(1): 12328, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112901

RESUMO

Boron has essential roles in plant growth and development. BOR proteins are key in the active uptake and distribution of boron, and regulation of intracellular boron concentrations. However, their mechanism of action remains poorly studied. BOR proteins are homologues of the human SLC4 family of transporters, which includes well studied mammalian transporters such as the human Anion Exchanger 1 (hAE1). Here we generated Arabidopsis thaliana BOR1 (AtBOR1) variants based (i) on known disease causing mutations of hAE1 (S466R, A500R) and (ii) a loss of function mutation (D311A) identified in the yeast BOR protein, ScBOR1p. The AtBOR1 variants express in yeast and localise to the plasma membrane, although both S466R and A500R exhibit lower expression than the WT AtBOR1 and D311A. The D311A, S466R and A500R mutations result in a loss of borate efflux activity in a yeast bor1p knockout strain. A. thaliana plants containing these three individual mutations exhibit substantially decreased growth phenotypes in soil under conditions of low boron. These data confirm an important role for D311 in the function of the protein and show that mutations equivalent to disease-causing mutations in hAE1 have major effects in AtBOR1. We also obtained a low resolution cryo-EM structure of a BOR protein from Oryza sativa, OsBOR3, lacking the 30 C-terminal amino acid residues. This structure confirms the gate and core domain organisation previously observed for related proteins, and is strongly suggestive of an inward facing conformation.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/genética , Antiporters/genética , Proteínas de Arabidopsis/genética , Proteínas de Membrana Transportadoras/genética , Desenvolvimento Vegetal/genética , Proteínas de Saccharomyces cerevisiae/genética , Antiporters/ultraestrutura , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/ultraestrutura , Boratos/metabolismo , Boro/metabolismo , Regulação da Expressão Gênica de Plantas , Humanos , Transporte de Íons/genética , Mutação , Oryza/genética , Oryza/crescimento & desenvolvimento , Saccharomyces cerevisiae/genética
11.
ACS Appl Mater Interfaces ; 13(24): 29113-29121, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34105349

RESUMO

The efficient and bioorthogonal chemical ligation reaction between potassium acyltrifluoroborates (KATs) and hydroxylamines (HAs) was used for the surface functionalization of a self-assembled monolayer (SAM) with biomolecules. An alkane thioether molecule with one terminal KAT group (S-KAT) was synthesized and adsorbed onto a gold surface, placing a KAT group on the top of the monolayer (KAT-SAM). As an initial test case, an aqueous solution of a hydroxylamine (HA) derivative of poly(ethylene glycol) (PEG) (HA-PEG) was added to this KAT-SAM at room temperature to perform the surface KAT ligation. Quartz crystal microbalance with dissipation (QCM-D) monitoring confirmed the rapid attachment of the PEG moiety onto the SAM. By surface characterization methods such as contact angle and ellipsometry, the attachment of PEG layer was confirmed, and covalent amide-bond formation was established by X-ray photoelectron spectroscopy (XPS). In a proof-of-concept study, the applicability of this surface KAT ligation for the attachment of biomolecules to surfaces was tested using a model protein, green fluorescent protein (GFP). A GFP was chemically modified with an HA linker to synthesize HA-GFP and added to the KAT-SAM under aqueous dilute conditions. A rapid attachment of the GFP on the surface was observed in real time by QCM-D. Despite the fact that such biomolecules have a variety of unprotected functional groups within their structures, the surface KAT ligation proceeded rapidly in a chemoselective manner. Our results demonstrate the versatility of the KAT ligation for the covalent attachment of a variety of water-soluble molecules onto SAM surfaces under dilute and biocompatible conditions to form stable, natural amide bonds.


Assuntos
Boratos/química , Proteínas de Fluorescência Verde/química , Proteínas Imobilizadas/química , Membranas Artificiais , Hidroxilaminas/química , Polietilenoglicóis/química , Estudo de Prova de Conceito
12.
Environ Sci Process Impacts ; 23(7): 1006-1017, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34105591

RESUMO

The development of nanoagrochemicals has attracted much attention in the last decade to overcome the recent agricultural and environmental challenges associated with the intensive usage of insecticides. Herein, nanostructured calcium borate materials with hierarchical sea urchin-like microspheres and microblocks have been synthesized by a facile hydrothermal method. The insecticidal activity of CaB2O4 and its synergistic combination with cholinesterase-inhibiting insecticides are explored against Spodoptera littoralis (S. littoralis) for the first time via a feeding bioassay protocol. The insecticidal efficacy of sea urchin-like microspheres (CB-A) is estimated to be LC50 = 207 mg L-1 which is two-fold higher than that of microblocks (CBM-A) with LC50 = 406 mg L-1 after eleven days of exposure. The synergistic combination of the CB-A sample with methomyl and chlorpyrifos increases the toxicity to 2.4 and 2.6-fold higher than that of the individual insecticides, respectively. Significantly, sea urchin-like CaB2O4 microspheres cause physical damage to the external insect's cuticle layer, which consequently enhances the uptake of organic insecticides. Our results revealed that calcium borate micro-/nano-structures can be employed as a multifunctional nanoagrochemical in various agricultural programs for S. littoralis control and decrease the usage of cholinesterase-inhibiting insecticides.


Assuntos
Inseticidas , Animais , Boratos , Compostos de Cálcio , Colinesterases , Inseticidas/toxicidade , Larva , Microesferas , Ouriços-do-Mar , Spodoptera
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120044, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118522

RESUMO

Fluorescent probes have contributed greatly to our understanding of the biological role of peroxynitrite (ONOO-). The ONOO- fluorescence probe characterized by the arlyboronate received a moderate opening fluorescence response, and the borate-masked probe significantly increased the sensitivity of ONOO-. Thus, two simple fluorescent probes (ADB and ANB) with the recognition receptor of phenyl boronate moiety were constructed for the detection of ONOO-. The change of emission spectrum was affected differently by the electron donating (or withdrawing) of the substituents. ANB was shown to have a low sensitivity and quantum yield towards ONOO- in aqueous solution, whereas ADB with aggregation-induced emission (AIE) process exhibited not only good sensitivity for ONOO- with a detection limit of 75 nM, but also ADB could be used to quantitative detecting ONOO- in response to concentrations of ONOO- within 20 s. Importantly, ADB had good performance for the detection of exogenous ONOO- in the RAW 264.7 cells.


Assuntos
Corantes Fluorescentes , Ácido Peroxinitroso , Animais , Boratos , Camundongos , Imagem Óptica , Células RAW 264.7
14.
J Hazard Mater ; 419: 126402, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34157467

RESUMO

Radioactive borate waste containing a high concentration of boron (B) is problematic to be solidified using cement because soluble borate such as boric acid hinders the hydration reaction. In this study, borate waste was used as a raw material for metakaolin-based geopolymer according to the characteristic that B replaces a part of Si. Geopolymers using KOH alkaline activator (K-geopolymers) showed higher compressive strength than geopolymers using NaOH alkaline activator (Na-geopolymer). In addition, the compressive strength increased proportionally to the Si/(Al+B) ratio regardless of the alkaline cation species. These variations in compressive strength might be due to the viscosity of the geopolymer mixture, atomic size of alkaline cations, and the increase in Si content. The characteristic analyses (XRD, FT-IR, and solid state 11B MAS NMR) indicated that B was incorporated into the geopolymer structure. Thus, the K-geopolymer has a dense and homogeneous microstructure. In a semi-dynamic leaching test, less B leached from the geopolymers compared to the cement waste form. Consequently, borate waste can be solidified using metakaolin-based geopolymer, and the use of a KOH alkaline activator is advantageous in terms of mechanical property and structural durability.


Assuntos
Resíduos Radioativos , Boratos , Força Compressiva , Materiais de Construção , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Anal Chem ; 93(26): 9267-9276, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34165952

RESUMO

Recent progress in the development and production of new, innovative protein therapeutics require rapid and adjustable high-resolution bioseparation techniques. Sodium dodecyl sulfate capillary gel electrophoresis (SDS-CGE) using a borate (B) cross-linked dextran (D) separation matrix is widely employed today for rapid consistency analysis of therapeutic proteins in manufacturing and release testing. Transient borate cross-linking of the semirigid dextran polymer chains leads to a high-resolution separation gel for SDS-protein complexes. To understand the migration and separation basis of the D/B gel, the present work explores various gel formulations of dextran monomer (2, 5, 7.5, and 10%) and borate cross-linker (2 and 4%) concentrations. Ferguson plots were analyzed for a mixture of protein standards with molecular weights ranging from 20 to 225 kDa, and the resulting nonlinear concave curves pointed to nonclassical sieving behavior. While the 2% D/4% B gel resulted in the fastest analysis time, the 10% D/2% B gel was found to produce the greatest separation window, even higher than with the 10% D/4% B gel, due to a significant increase in the electroosmotic flow of the former composition in the direction opposite to SDS-protein complex migration. The study then focused on SDS-CGE separation of a therapeutic monoclonal antibody and its subunits. A combination of molecular weight and shape selectivity as well as, to a lesser extent, surface charge density differences (due to glycosylation on the heavy chain) influenced migration. Greater molecular weight selectivity occurred for the higher monomer concentration gels, while improved glycoselectivity was obtained using a more dilute gel, even as low as 2% D/2% B. This latter gel took advantage of the dextran-borate-glycoprotein complexation. The study revealed that by modulating the dextran (monomer) and borate (cross-linker) concentration ratios of the sieving matrix, one can optimize the separation for specific biopharmaceutical modalities with excellent column-to-column, run-to-run, and gel-to-gel migration time reproducibilities (<0.96% relative standard deviation (RSD)). The widely used 10% dextran/4% borate gel represents a good screening option, which can then be followed by a modified composition, optimized for a specific separation as necessary.


Assuntos
Boratos , Dextranos , Eletroforese Capilar , Eletroforese em Gel de Poliacrilamida , Géis , Peso Molecular , Dodecilsulfato de Sódio
16.
J Mater Chem B ; 9(20): 4230-4240, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33998631

RESUMO

Multifunctional hydrogels that integrate stretchability, adhesion, self-healing, and antibacterial properties may find use in a variety of fields including electronic skin, wound dressings, and wearable devices; however, traditional hydrogels often exhibit short-term adhesiveness, poor mechanical properties, and a lack of antibacterial activity. Herein, a plant-inspired polyacrylamide-soybean protein isolate-pyrogallol/borax (PAM-SPI-P/B) hydrogel has been developed using a facile green method based on dynamic coordination cross-linking between pyrogallol (PG) and borax. The PG-borax dynamic bonds adjusted the network structure of the hydrogels to provide greater structural integrity to the PAM-SPI double network. This hydrogel possessed a high mechanical strength (large elongation up to 760% and compressive strength up to 1.25 MPa at 80% strain), low swelling ratio, and self-healing properties. Inspired by natural polyphenols that contain adhesive molecules, the addition of pyrogallol provided the hydrogel excellent adhesion to various hydrophilic and hydrophobic substrates. And with the inhibition of pyrogallol autoxidation due to the borax protection, the hydrogel showed repeatable and durable adhesion over 20 cycles. The obtained hydrogels also exhibited good antibacterial activities against Escherichia coli and Staphylococcus aureus because they were based on pyrogallol and borax, which have antibacterial properties. Accordingly, we envision that the PAM-SPI-P/B hydrogels have great potential for use in biomimetic tissues and biosensors.


Assuntos
Antibacterianos/farmacologia , Boratos/farmacologia , Reagentes para Ligações Cruzadas/farmacologia , Hidrogéis/farmacologia , Pirogalol/farmacologia , Adesinas Bacterianas/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Boratos/química , Reagentes para Ligações Cruzadas/síntese química , Reagentes para Ligações Cruzadas/química , Escherichia coli/efeitos dos fármacos , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pirogalol/química , Staphylococcus aureus/efeitos dos fármacos
17.
Org Lett ; 23(11): 4289-4293, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34029464

RESUMO

Stereoselective reactions at the anomeric carbon constitute the cornerstone of preparative carbohydrate chemistry. Here, we report stereoselective C-arylation and etherification reactions of anomeric trifluoroborates derived from BMIDA esters. These reactions are characterized by high anomeric selectivities for 2-deoxysugars and broad substrate scope (24 examples), including disaccharides and trifluoroborates with free hydroxyl groups. Taken together, this new class of carbohydrate reagents adds the palette of anomeric nucleophile reagents suitable for efficient installation of C-C bonds.


Assuntos
Boratos/química , Carbono/química , Dissacarídeos/síntese química , Dissacarídeos/química , Ésteres , Estrutura Molecular , Estereoisomerismo
18.
Mater Sci Eng C Mater Biol Appl ; 123: 112003, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33812623

RESUMO

Muscle tissue possess an innate regenerative potential that involves an extremely complicated and synchronized process on which resident muscle stem cells play a major role: activate after an injury, differentiate and fuse originating new myofibers for muscle repair. Considerable efforts have been made to design new approaches based on material systems to potentiate muscle repair by engineering muscle extracellular matrix and/or including soluble factors/cells in the media, trying to recapitulate the key biophysical and biochemical cues present in the muscle niche. This work proposes a different and simple approach to potentiate muscle regeneration exploiting the interplay between specific cell membrane receptors. The simultaneous stimulation of borate transporter, NaBC1 (encoded by SLC4A11gene), and fibronectin-binding integrins induced higher number and size of focal adhesions, major cell spreading and actin stress fibers, strengthening myoblast attachment and providing an enhanced response in terms of myotube fusion and maturation. The stimulated NaBC1 generated an adhesion-driven state through a mechanism that involves simultaneous NaBC1/α5ß1/αvß3 co-localization. We engineered and characterized borax-loaded alginate hydrogels for an effective activation of NaBC1 in vivo. After inducing an acute injury with cardiotoxin in mice, active-NaBC1 accelerated the muscle regeneration process. Our results put forward a new biomaterial approach for muscle repair.


Assuntos
Alginatos , Hidrogéis , Animais , Boratos , Hidrogéis/farmacologia , Camundongos , Regeneração
19.
Biosens Bioelectron ; 184: 113230, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33872980

RESUMO

Blood lead poisoning is a universal and severe health problem that greatly threatens human health in various industries. Elimination of blood lead relying on chelating agents and combination with hemoperfusion adsorbents has achieved considerable progress, but it is still suffering from the compromised selectivity of adsorbents as well as in absence of real time monitoring during treatment. Herein, we proposed a selective blood lead adsorbent integrated with real-time visualized/electrochemical bi-modal monitoring based on TMPyP-bound guanosine-borate (GB) supramolecular hydrogel as potential smart hemoperfusion device. The GB hydrogel possessed stability in physiological environment, self-healing ability resistant to fluid shear, blood compatibility, selective adsorption of lead ions superior to conventional adsorbents, anti-fouling performance to blood components and renewability. Benefiting from binding with TMPyP and the intrinsic conductivity, GB hydrogel was endowed with the ability to qualitatively diagnose the presence of blood lead via simple color change and quantitatively reflect the amount of adsorbed lead from blood accurately through electrochemical technique. This work puts forward an integrated treatment/monitoring hemoperfusion device with high selectivity, simple fabrication and low-cost, providing a paradigm for next generation design of intelligent, monitorable theranostic hemopurification system, which is also an extensible platform for the other research fields such as environmental monitoring and remediation.


Assuntos
Técnicas Biossensoriais , Hemoperfusão , Boratos , Guanosina , Humanos , Hidrogéis , Chumbo
20.
Int J Biol Macromol ; 182: 1179-1191, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33895176

RESUMO

Polysaccharides-based hydrogel has many advantages such as biocompatibility, self-repair property, and biodegradability. It has been widely applied in various fields and has attracted great attention of researchers. The natural polysaccharides involved in this review include fenugreek gum, guar gum, locust bean gum, gellan gum, sodium alginate, agarose, and konjac glucomannan etc. Borax is a highly effective crosslinking agent for cis-ortho-hydroxyl polysaccharides. This paper focused on the synthesis mechanism, functional additives, characteristics, and applications of borax crosslinked cis-ortho-hydroxyl polysaccharides hydrogels (BHs). Moreover, the factors affecting BHs performance such as temperature, pH, and media were analyzed. Its mechanical and self-repair properties are enhanced by the dynamic and reversible borate/di-diol, which play a significant role in sensors, biomedicine, and tissue engineering. This review summarizes the research progress of BHs for the first time. Additionally, hoping to contribute to the development of this field, the review analyzes the correlation of performance through the SPSS 26 software.


Assuntos
Boratos/química , Hidrogéis/química , Polissacarídeos/química , Prótons , Temperatura , Engenharia Tecidual
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