RESUMEN
Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibers embedded with borate glasses of 45B5 composition doped with Co2+, Cu2+, and Zn2 +(46.1 B2O326.9-X CaO24.4 Na2O2.6 P2O5, X CoO/CuO/ZnO mol % (X = 0-5)) were produced by electrospinning for wound healing applications. Prior to their addition, the glasses exhibited two broad halos typical of a vitreous borate network, which were mainly composed of ring-type metaborate structural units. The particle distribution in the PHBV nanofibers embedded with 45B5 borate bioactive glasses is present in isolated and agglomerated states, being partially coated by a polymeric layer-except for the cobalt-doped glass, which resulted in a successful encapsulation with 100% embedding efficiency. The incorporation of the glasses reduced the PHBV crystallinity degree and its decomposition temperature, as well as its mechanical properties, including Young's modulus, tensile strength, and elongation at break. The neat PHBV fibers and those containing the cobalt-doped glasses demonstrated great cytocompatibility with human keratinocytes (HaCat), as suggested by the high cell viability after 7 days of exposure. Further studies are needed to fully understand the wound healing potential of these fibers, but our results significantly contribute to the area.
Asunto(s)
Vendajes , Boratos , Cobalto , Cobre , Poliésteres , Zinc , Humanos , Cobre/química , Cobalto/química , Poliésteres/química , Boratos/química , Zinc/química , Vidrio/química , Ensayo de Materiales , Cicatrización de Heridas , Nanofibras/química , Línea Celular , PolihidroxibutiratosRESUMEN
In the present study, we have prepared six glass samples of bismuth borate using the melt-quenching method with the composition (70-x)B2O3-10CaO-20Na2O-xBi2O3; x = 0, 3, 6, 9, 12 and 15 mol%. The density of the prepared glasses was determined using Archimedes principle. The X-ray diffraction patterns provide confirmation of the amorphous nature of the prepared samples, whereas the Fourier transform infrared measurements pointed to the existence of structural units like BO3, BO4, BiO3 and BiO6 within the glass network. An assessment of the optical absorption spectra unveiled that with the increase in the bismuth oxide content, there was a decrease observed in both the direct and indirect band gap energies. Specifically, they decreased from 3.40 to 2.79 eV and from 3.10 to 2.46 eV, respectively. The properties related to gamma ray attenuation, including the mass attenuation coefficient (µm), effective atomic number (Zeff), half-value layer (HVL) and mean free path (MFP), were examined for all the glass samples. This investigation was carried out using the Phy-X/PSD software, covering the energy range from 0.511 to 1.332 MeV. Out of all the samples, Bi-15, featuring the highest Bi2O3 content, demonstrated the highest µm, Zeff, the smallest HVL and MFP. These results suggest that the glass with 15 mol% of Bi2O3 offers the most effective gamma radiation shielding performance. Moreover, the glasses examined in this study exhibit superior radiation shielding characteristics compared with specific concrete types, namely, ordinary concrete, Hematite serpentine concrete and barite concrete, as well as commercial glasses such as RS-360 and RS-253.
Asunto(s)
Bismuto , Boratos , Rayos gamma , Vidrio , Protección Radiológica , Bismuto/química , Vidrio/química , Boratos/química , Protección Radiológica/métodos , Calcio/química , Sodio/química , Difracción de Rayos X , Ensayo de Materiales , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Sandy soils are suffering from water loss and desertification, which severely restrict the development of local agriculture. In this work, an eco-friendly hydrogel composed of borax and locust bean gum was synthesized to enhance the water retention capacity of sandy soil and support agricultural development in arid regions. Locust bean gum/borax hydrogel with a 3D network structure exhibited great water-absorbing capacity (130.29 g/g) within 30 min. After mixing 0.9 wt% hydrogel with sandy soil, the maximum soil water content, water retention time, soil porosity and soil organic matter were increased by 32.03 %, 14 days, 38.9 % and 8.64 g/kg respectively. Little effect on soil microorganisms revealed barely toxicity. Furthermore, the hydrogel was confirmed to be biodegradable at 43.47 % after 4 weeks. According to the study, locust bean gum/borax hydrogel possesses good water absorbing capacity, soil water retention ability, soil optimization ability and low adverse environmental impact. Together, it is inferred that the hydrogel can improve the water retention capacity of sandy soil in arid areas, promoting plant growth in arid areas.
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Galactanos , Hidrogeles , Mananos , Gomas de Plantas , Suelo , Agua , Gomas de Plantas/química , Galactanos/química , Mananos/química , Suelo/química , Agua/química , Hidrogeles/química , Porosidad , Arena/química , Biodegradación Ambiental , Microbiología del Suelo , BoratosRESUMEN
Chemical oxo-precipitation (COP) is an enhanced precipitation method for boron removal with the conversion of boric acid to perborate anions. When using barium-based precipitant, the boron can be effectively precipitated as barium perborates (BaPBs). The phase transformation of BaPBs from amorphous (A-BaPB, Ba(B(OH)3OOH)2) to crystalline (C-BaPB, BaB2(OO)2(OH)4) form is crucial for effective boron removal. However, scaling up this phase transformation of BaPBs is hindered by poor diffusion. This study aims to promote the growth of C-BaPB through seed-induced crystal growth, eliminating the need for phase transformation. By examining the relationship between crystal growth rate and supersaturation, surface spiral growth was identified as the rate-limiting step of the growth of micron-sized seeds near pHpzc. To enable continuous crystal growth, granular seeds of C-BaPB were prepared and employed as the medium for fluidized-bed crystallization (FBC). The system reached steady state 3 hydraulic retention times, achieving 90% boron removal. The effect of surface loading, ionic strength, and dosages on steady-state crystal growth rate was studied, revealing a shift of the rate-limiting step in FBC to diffusion. Lastly, the system that constituted of two FBCs in-series for sequential crystallization of A-BaPB and C-BaPB was demonstrated. The integrated system provided 97.8% of boron removal from synthetic wastewater containing 500 mg-B/L, with 92.3% of boron crystallized on the granular seeds of BaPBs.
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Bario , Boro , Cristalización , Boro/química , Bario/química , Boratos/química , Precipitación Química , Contaminantes Químicos del Agua/químicaRESUMEN
This study evaluated the effectiveness of using nanocomposite (NCs) of xanthan gum grafted polyacrylamide crosslinked Borax - iron oxide nanoparticle (XG-g-pAAm-CL-Borax-IONP) to remove the amoxicillin antibiotic (AMX) from an aquatic environment. To confirm the structural characteristics of the prepared XG-g-pAAm-CL-Borax-IONP NCs, unique characterization methods (XRD, FT-IR, FE-SEM, EDX, BET, TGA, Zeta, and VSM) were used. Adsorption experimental setups were performed with the influence of solution pH (4-9), the effect of adsorbent dose (0.003-0.02 g), the effect of contact time (5-45 min), and the effect of initial AMX concentration (50-400 mg/L) to achieve the most efficient adsorption conditions. Based on the Freundlich isotherm model, XG-g-pAAm-CL-Borax-IONP NCs provided the maximum AMX adsorption capacity of 1183.639 mg/g. This research on adsorption kinetics also established that the pseudo-second-order model (R2 = 0.991) is outstanding compatibility with the experimental results. AMX adsorption on the NCs may occur through intermolecular hydrogen bonding, diffusion, and trapping into the polymer network. Even after five cycles, these NCs still displayed the best performance. Based on these results, XG-g-pAAm-CL-Borax-IONP NCs may be a viable material for the purification of AMX from contaminated water.
Asunto(s)
Resinas Acrílicas , Amoxicilina , Boratos , Nanocompuestos , Polisacáridos Bacterianos , Contaminantes Químicos del Agua , Nanocompuestos/química , Contaminantes Químicos del Agua/química , Resinas Acrílicas/química , Amoxicilina/química , Polisacáridos Bacterianos/química , Adsorción , Boratos/química , Cinética , Antibacterianos/química , Purificación del Agua/métodos , Concentración de Iones de HidrógenoRESUMEN
Ionic liquids (ILs) become emerging environmental pollutants. Especially, alkyl imidazolium ILs commonly showed stimulation in toxicological studies and mechanisms remained to be explored. In the present study, alkyl imidazolium tetrafluoroborate ([amim]BF4), with ethyl ([emim]), hexyl ([hmim]) and octyl ([omim]) as side-chains, were chosen as target ILs. Their toxicities on the reproduction and lifespan of Caenorhabditis elegans were explored with two types (A and B) exposure arrangements to mimic realistic intermittent multi-generational exposure scenarios. In type A scenario, there was an exposure every 4 generations with 12 generations in total, and in type B one, there was an exposure every two generations with 12 generations in total. Result showed that [emim]BF4 caused inhibition on the reproduction in 8 generations in type A exposure but 6 ones in type B exposure. Meanwhile, [hmim]BF4 showed inhibition in one generation and stimulation in 3 generations in type A exposure, but stimulation in 6 generations in type B exposure. Also, [omim]BF4 showed stimulation in one generation in type B exposure. Collectively, the results demonstrated less frequencies of inhibition, or more frequencies of stimulation, in the exposure scenario with more frequent exposures. Further mechanism exploration was performed to measure the lipid storage and metabolism in the aspect of energy supply. Results showed that [emim]BF4, [hmim]BF4 and [omim]BF4 commonly stimulated the triglyceride (TG) levels across generations. They also disturbed the activities of glycerol-3-phosphate acyltransferase (GPAT) and acetyl CoA carboxylase (ACC) in lipogenesis, those of adipose triglyceride lipase (ATGL) and carnitine acyl transferase (CPT) in lipolysis, and also the contents of acetyl-CoA (ACA). Further data analysis indicated the energy allocation among life traits including reproduction, antioxidant responses and hormone regulations.
Asunto(s)
Caenorhabditis elegans , Imidazoles , Líquidos Iónicos , Metabolismo de los Lípidos , Reproducción , Animales , Caenorhabditis elegans/efectos de los fármacos , Caenorhabditis elegans/fisiología , Metabolismo de los Lípidos/efectos de los fármacos , Imidazoles/toxicidad , Reproducción/efectos de los fármacos , Líquidos Iónicos/toxicidad , Contaminantes Ambientales/toxicidad , Boratos/toxicidadRESUMEN
The detections of H2O2 and catalase play an important role in daily life. This study introduces a paper-based flow sensor that is specifically designed to detect H2O2 and catalase. The sensor utilizes a hydrogel composed of cross-linked 4-carboxyphenylboronic acid and polyvinyl alcohol. When H2O2 is in contact with the hydrogel, the B-C bonds of the hydrogel undergo a reactive process, causing decomposition of the hydrogel. The pH indicator strip enables the visual monitoring of the viscosity change that occurs during the gel-sol transition. The quantification of H2O2 is accomplished by assessing the proportion of water coverage on the pH indicator strip. The sensor shows a detection limit of 0.077 wt% and is applicable for the quantitative measurement of H2O2 in routinely used disinfectants. Furthermore, the presence of catalase is effectively identified and the detection of catalase in milk is successfully fulfilled. In summary, this work proposes a simple, user-friendly, label-free, and cost-effective method for constructing a paper-based flow sensor using borate cross-linked polyvinyl alcohol hydrogel, showing great potential for detecting H2O2 and catalase in various practical scenarios.
Asunto(s)
Boratos , Catalasa , Peróxido de Hidrógeno , Papel , Alcohol Polivinílico , Peróxido de Hidrógeno/análisis , Peróxido de Hidrógeno/química , Alcohol Polivinílico/química , Catalasa/química , Boratos/química , Hidrogeles/química , Animales , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Leche/química , Límite de Detección , Reactivos de Enlaces Cruzados/química , Concentración de Iones de HidrógenoRESUMEN
Orodispersible films (ODFs) have emerged as an advanced and patient-friendly delivery system due to ease of administration, improved patient compliance, quick release and taste-masking of active pharmaceutical ingredients. This research reports the preparation of the ODF containing eugenol and borax (EB-ODF) by a solvent casting technique for treating mouth ulcers. The EB-ODF consisted of vinyl pyrrolidone/vinyl acetate copolymer (Kollidon® VA64, VA64) and hydroxypropyl methylcellulose (HPMC-K250) as the film formers where eugenol and borax were loaded. The thickness of the EB-ODF obtained was 0.119 ± 0.001 mm and the tensile strength was 13.1 ± 1.1 N/mm2 (p > 0.05). The prepared films disintegrated in the oral cavity within 30 s and over 90% of the eugenol was released from the film in the first 5 min. Furthermore, the combined application of eugenol and borax, loaded in EB-ODF, displayed notable synergetic antibacterial property against both gram-negative and gram-positive bacteria. In an in-vivo study on a rat model with chemical burn-induced oral ulcers, the EB-ODF treatment group had a 100% reduction in ulcer area (p > 0.05) after 10 days of treatment and demonstrated a 38.7% higher reduction in oral ulcer area compared to the Dingpeng Cream treatment group (p < 0.0001). The EB-ODF treatment group showed minimal oral irritation, scoring only 1 point and a 65% preference in the taste tests (p < 0.0001). In summary, EB-ODF had successfully overcome the poor palatability of commercially available formulation and provided notable potential for further ulcer treatment product development.
Asunto(s)
Boratos , Eugenol , Úlceras Bucales , Eugenol/administración & dosificación , Eugenol/farmacología , Animales , Ratas , Boratos/administración & dosificación , Úlceras Bucales/tratamiento farmacológico , Masculino , Administración Oral , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Derivados de la Hipromelosa/química , Ratas Wistar , Resistencia a la TracciónRESUMEN
Perhalogenated closo-borates represent a new class of membrane carriers. They owe this activity to their chaotropicity, which enables the transport of hydrophilic molecules across model membranes and into living cells. The transport efficiency of this new class of cluster carriers depends on a careful balance between their affinity to membranes and cargo, which varies with chaotropicity. However, the structure-activity parameters that define chaotropic transport remain to be elucidated. Here, we have studied the modulation of chaotropic transport by decoupling the halogen composition from the boron core size. The binding affinity between perhalogenated decaborate and dodecaborate clusters carriers was quantified with different hydrophilic model cargos, namely a neutral and a cationic peptide, phalloidin and (KLAKLAK)2. The transport efficiency, membrane-lytic properties, and cellular toxicity, as obtained from different vesicle and cell assays, increased with the size and polarizability of the clusters. These results validate the chaotropic effect as the driving force behind the membrane transport propensity of boron clusters. This work advances our understanding of the structural features of boron cluster carriers and establishes the first set of rational design principles for chaotropic membrane transporters.
Asunto(s)
Boro , Boro/química , Boro/metabolismo , Humanos , Transporte Biológico , Compuestos de Boro/química , Compuestos de Boro/metabolismo , Interacciones Hidrofóbicas e Hidrofílicas , Boratos/química , Boratos/metabolismoRESUMEN
Preventing bacterial infections is a crucial aspect of wound healing. There is an urgent need for multifunctional biomaterials without antibiotics to promote wound healing. In this study, we fabricated a guar gum (GG)-based nanocomposite hydrogel, termed GBTF, which exhibited photothermal antibacterial therapy for infected wound healing. The GBTF hydrogel formed a cross-linked network through dynamic borate/diol interactions between GG and borax, thereby exhibiting simultaneously self-healing, adaptable, and injectable properties. Additionally, tannic acid (TA)/Fe3+ nanocomplexes (NCs) were incorporated into the hydrogel to confer photothermal antibacterial properties. Under the irradiation of an 808 nm near-infrared laser, the TA/Fe3+ NCs in the hydrogel could rapidly generate heat, leading to the disruption of bacterial cell membranes and subsequent bacterial eradication. Furthermore, the hydrogels exhibited good cytocompatibility and hemocompatibility, making them a precandidate for preclinical and clinical applications. Finally, they could significantly promote bacteria-infected wound healing by reducing bacterial viability, accelerating collagen deposition, and promoting epithelial remodeling. Therefore, the multifunctional GBTF hydrogel, which was composed entirely of natural substances including guar gum, borax, and polyphenol/ferric ion NCs, showed great potential for regenerating infected skin wounds in clinical applications.
Asunto(s)
Antibacterianos , Galactanos , Hidrogeles , Mananos , Nanocompuestos , Terapia Fototérmica , Gomas de Plantas , Cicatrización de Heridas , Mananos/química , Mananos/farmacología , Gomas de Plantas/química , Gomas de Plantas/farmacología , Galactanos/química , Galactanos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Nanocompuestos/química , Hidrogeles/química , Hidrogeles/farmacología , Animales , Terapia Fototérmica/métodos , Ratones , Taninos/química , Taninos/farmacología , Staphylococcus aureus/efectos de los fármacos , Humanos , Escherichia coli/efectos de los fármacos , BoratosRESUMEN
In this study, sodium pentaborate pentahydrate (NaB) and Hypericum perforatum (HP) oil were incorporated into polyvinyl alcohol (PVA) and chitosan (CH) polymer blend to obtain membranes by solution casting method. In order to see the synergistic effects of NaB and HP oil on the biological and physical properties of the membranes NaB and HP oil were incorporated into membrane matrix in different ratios. Fourier-transform infrared spectroscopy (FTIR) results showed that no significant bond formation between the bioactive components and the PVA:CH matrix. According to mechanical test results, Young's Modulus and elongation at break decreased from 426 MPa to 346 MPa and 52.23 % to 15.11 % for neat PVA:CH membranes and NaB and HP oil incorporated PVA:CH (PVA:CH@35NaB:HP) membranes, respectively. Antimicrobial activity tests have shown the membranes were over 99 % effective against Escherichia coli, Staphylococcus aureus, and Candida albicans, underlining their potential for infection control. Cytocompatibility assay performed with Human Dermal Fibroblast (HDFa) cells highlight the biocompatibility of the membranes, revealing 74.84 % cell viability after 72 h. The properties of NaB and HP oil doped PVA:CH based membranes obtained from these experiments reveal the promise of a versatile membrane for applications in wound healing, tissue engineering and other biomedical fields.
Asunto(s)
Quitosano , Hypericum , Membranas Artificiales , Alcohol Polivinílico , Quitosano/química , Quitosano/farmacología , Hypericum/química , Alcohol Polivinílico/química , Humanos , Boratos/química , Boratos/farmacología , Aceites de Plantas/química , Aceites de Plantas/farmacología , Antiinfecciosos/farmacología , Antiinfecciosos/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Candida albicans/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Escherichia coli/efectos de los fármacos , Fibroblastos/efectos de los fármacosRESUMEN
Efficiently removing excess reactive oxygen species (ROS) generated by various factors on the ocular surface is a promising strategy for preventing the development of dry eye disease (DED). The currently available eye drops for DED treatment are palliative, short-lived and frequently administered due to the short precorneal residence time. Here, we developed nanozyme-based eye drops for DED by exploiting borate-mediated dynamic covalent complexation between n-FeZIF-8 nanozymes (n-Z(Fe)) and poly(vinyl alcohol) (PVA) to overcome these problems. The resultant formulation (PBnZ), which has dual-ROS scavenging abilities and prolonged corneal retention can effectively reduce oxidative stress, thereby providing an excellent preventive effect to alleviate DED. In vitro and in vivo experiments revealed that PBnZ could eliminate excess ROS through both its multienzyme-like activity and the ROS-scavenging activity of borate bonds. The positively charged nanozyme-based eye drops displayed a longer precorneal residence time due to physical adhesion and the dynamic borate bonds between phenyboronic acid and PVA or o-diol with mucin. The in vivo results showed that eye drops could effectively alleviate DED. These dual-function PBnZ nanozyme-based eye drops can provide insights into the development of novel treatment strategies for DED and other ROS-mediated inflammatory diseases and a rationale for the application of nanomaterials in clinical settings.
Asunto(s)
Síndromes de Ojo Seco , Soluciones Oftálmicas , Especies Reactivas de Oxígeno , Soluciones Oftálmicas/química , Soluciones Oftálmicas/farmacología , Síndromes de Ojo Seco/tratamiento farmacológico , Animales , Especies Reactivas de Oxígeno/metabolismo , Ratones , Estrés Oxidativo/efectos de los fármacos , Córnea/efectos de los fármacos , Córnea/metabolismo , Alcohol Polivinílico/química , Humanos , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Boratos/química , Nanopartículas/química , MasculinoRESUMEN
Borate glass transforms into hydroxycarbonate apatite more rapidly than silicate glass. This research aims to evaluate strontium's structural and biological effects on borate bioactive glass (BBG) and the influence of strontium concentrations (0%, 5%, 10%, and 15% Sr) prepared via the sol-gel method. The study reveals significant findings related to the physicochemical properties of the glass. Immersion of the glass powders in a simulated body fluid (SBF) led to the development of a hydroxyapatite (HAP) layer on the glass surfaces. This transformation was verified through X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) analyses. In particular, 5% strontium exhibited gradual degradation, resulting in particle sizes below 100 nm. The BBG-15%Sr demonstrates heightened pathogenic activity as it shows a significant inhibition zone of 14 mm at 250 µg/mL, surpassing other substituted BBGs. It effectively combats Gram-positive bacteria, completely inhibiting MRSA growth at 50 µg/mL. This underscores its robust biofilm disruption capabilities, eradicating biofilms, even at minimal concentrations after prolonged exposure. C. elegans when subjected to BBG-15%Sr shows less ROS production when compared with the others. Moreover, the results suggest that the modified glass could be a potential material for the treatment of osteomyelitis-affected bone repair.
Asunto(s)
Antibacterianos , Materiales Biocompatibles , Boratos , Vidrio , Ensayo de Materiales , Staphylococcus aureus Resistente a Meticilina , Osteomielitis , Estroncio , Estroncio/química , Estroncio/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Boratos/química , Boratos/farmacología , Vidrio/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/síntesis química , Osteomielitis/tratamiento farmacológico , Osteomielitis/microbiología , Tamaño de la Partícula , Pruebas de Sensibilidad Microbiana , Animales , Propiedades de SuperficieRESUMEN
Gestational diabetes mellitus (GDM) is one of the most common metabolic disorders during pregnancy, leading to serious complications for pregnant women and a threat to life safety of infants. Therefore, it is particularly important to establish a multipurpose monitoring pathway to important physiological indicators of pregnant women. In this work, three kinds of double network hydrogels are prepared with poly(vinyl alcohol) (PVA), borax, and cellulose ethers with varying substituents of methyl (methyl cellulose, MC), hydroxypropyl (hydroxypropyl cellulose, HPC), or both (hydroxypropyl methyl cellulose, HPMC), respectively. The corresponding toughness (143.9, 102.3, and 135.9 kJ cm-3) and conductivity (0.69, 0.45, and 0.51 S m-1) of the hydrogels demonstrate that PB-MC was endowed with the prominent performance. Molecular dynamics simulations further revealed the essence that hydrogen bond interactions between PVA and cellulose ethers play a critical role in regulating the structure and properties of hydrogels. Thermochromic capsule powders (TCPs) were subsequently doped in to achieve a composite hydrogel (TCPs@PB-MC) to indicate the change in human body temperature. Furthermore, the process of the TCPs@PB-MC response to glucose, pH, and temperature was tracked in-depth through the electrochemical window. This work provides a novel strategy for all-in-one health management of GDM.
Asunto(s)
Celulosa , Diabetes Gestacional , Hidrogeles , Alcohol Polivinílico , Femenino , Embarazo , Humanos , Hidrogeles/química , Celulosa/química , Celulosa/análogos & derivados , Alcohol Polivinílico/química , Boratos/química , Dispositivos Electrónicos Vestibles , Glucosa/química , Simulación de Dinámica Molecular , Temperatura , Concentración de Iones de Hidrógeno , Enlace de HidrógenoRESUMEN
STATEMENT OF PROBLEM: Denture stomatitis can pose serious health risks, especially to older people. Chemical denture cleaning agents must be effective, yet not adversely affect the longevity of removable dentures. Ready-to-use (RTU) neutral pH electrolyzed oxidizing water (EOW) is an effective biocide against Candida albicans biofilms on denture resins, but the effects of daily disinfection with EOW on the physical and mechanical properties of resins have not been established. PURPOSE: The purpose of this in vitro study was to investigate the effects of simulated long-term exposure to RTU EOW on the color, surface characteristics, and flexural strength of denture base resins. MATERIAL AND METHODS: Heat-polymerized (HP), 3D printed (3D) and computer-aided design and computer-aided manufacture (CAD-CAM)-milled (CC) denture resin specimens (square: 20×20×3.3 mm; beam: 64×10×3.3 mm) were immersed in tap water (TW), RTU EOW (Neutral Anolyte ANK; Envirolyte; EOW), or a commercial denture cleaning tablet solution (Polident 3-Minute; Glaxo SmithKline; PD), mimicking a 5-minute once daily disinfection routine performed up to 3.0 years. Color and surface roughness were recorded (n=3, squares), and changes in color (∆E00) and surface roughness (∆Ra) were calculated. Flexural strength (n=12, beams) and surface hardness (n=18, beams) were measured with a universal testing machine. The fractured surfaces of specimens were examined by scanning electron microscopy and energy dispersive spectroscopy. Data were assessed by performing the Shapiro-Wilk or D'Agostino and Pearson normality tests. Two-way ANOVA or the Kruskal-Wallis test with a post hoc Tukey HSD or Dunn multiple comparisons (α=.05) was used for statistical analyses. RESULTS: No significant changes were found in either color or surface roughness for HP, 3D, and CC resins after 1.5-year and 3.0-year immersion in any of the agents (P>.05). The surface hardness of 3D resins reduced by 14% with TW and by 23% with EOW and PD at 3.0 years. The flexural strengths of all 3 resins were unaffected by 3.0-year immersion (P>.05). CONCLUSIONS: Simulated long-term immersion disinfection with RTU neutral pH EOW did not adversely affect the physical and mechanical properties of HP or CC denture resins.
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Bases para Dentadura , Limpiadores de Dentadura , Propiedades de Superficie , Agua , Agua/química , Concentración de Iones de Hidrógeno , Limpiadores de Dentadura/química , Ensayo de Materiales , Resistencia Flexional , Humanos , Materiales Dentales/química , Diseño Asistido por Computadora , Técnicas In Vitro , Electrólisis , Resinas Acrílicas/química , Color , Boratos , SulfatosRESUMEN
The clinical translation of polysarcosine (pSar) as polyethylene glycol (PEG) replacement in the development of novel nanomedicines creates a broad demand of polymeric material in high-quality making high-purity sarcosine N-carboxyanhydride (Sar-NCA) as monomer for its production inevitable. Within this report, we present the use of triethyloxonium tetrafluoroborate in Sar-NCA synthesis with focus on amino acid and chloride impurities to avoid the sublimation of Sar-NCAs. With a view towards upscaling into kilogram or ton scale, a new methodology of monomer purification is introduced by utilizing the Meerwein's Salt triethyloxonium tetrafluoroborate to remove chloride impurities by covalent binding and converting chloride ions into volatile products within a single step. The novel straightforward technique enables access to monomers with significantly reduced chloride content (<100â ppm) compared to Sar-NCA derived by synthesis or sublimation. The derived monomers enable the controlled-living polymerization in DMF and provide access to pSar polymers with Poisson-like molecular weight distribution within a high range of chain lengths (Xn 25-200). In conclusion, the reported method can be easily applied to Sar-NCA synthesis or purification of commercially available pSar-NCAs and eases access to well-defined hetero-telechelic pSar polymers.
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Cloruros , Polimerizacion , Sarcosina , Sarcosina/química , Sarcosina/análogos & derivados , Cloruros/química , Polietilenglicoles/química , Polímeros/química , Boratos/química , Anhídridos/química , PéptidosRESUMEN
Developing high-performance hydrogels with anti-freeze, and antimicrobial properties is crucial for the practical application of flexible sensors. In this study, we prepared silver nanoparticles (AgNPs) with aloe polysaccharide (AP) as a reducing agent. Then, the AP/AgNPs were added to a system of polyvinyl alcohol and borax crosslinked in water/glycerol to obtain a multifunctional conductive hydrogel. The incorporated AgNPs improved the conductivity (0.39 S/m) and mechanical properties (elongation at break: 732.9 %, fracture strength: 1267.6 kPa) of the hydrogel. In addition, resultant hydrogel exhibited potential for sensing strain, temperature, and humidity. When used as a strain sensor, the hydrogel system exhibited low detection limit (0.1 %), and fast response (0.08 s). The resistance of the hydrogel decreased with an increase in the absorbed moisture content, enabling humidity detection (25-95 %) to monitor breathing status. As a temperature sensor, the hydrogel supported a wide detection range (-50 to +90 °C) and sensitivity (-30-0 °C, temperature coefficient of resistance (TCR) = -5.64 %/°C) to detect changes in the ambient temperature. This study proposes a simple method for manufacturing multifunctional hydrogel sensors, which broadens their application prospects in wearable sensing and electronic products.
Asunto(s)
Aloe , Hidrogeles , Nanopartículas del Metal , Nanocompuestos , Polisacáridos , Plata , Plata/química , Nanopartículas del Metal/química , Aloe/química , Polisacáridos/química , Nanocompuestos/química , Hidrogeles/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Temperatura , Humedad , BoratosRESUMEN
Borax is strictly regulated in the food processing and pharmaceutical industry due to its physiological toxicity, and the development of a direct analytical method is essential for effectively monitoring the borax abuse. In this work, the fluorescence properties of flavonoids, including flavones, isoflavones and flavonols, were systematically investigated from aqueous to borax solutions, and it was found that the weak intrinsic fluorescence of flavonols could be pervasively sensitized by borax. A natural flavonol, morin, was subsequently chosen as a representative probe to develop a turn-on fluorescence sensing method for borax analysis, which achieved a linear response spanning four orders of magnitude with a detection limit of 1.07 µM (0.22 µg mL-1 in terms of Na2B4O7 content). Furthermore, a smartphone-assisted paper-based test device was designed and constructed by 3D printing technology. Using morin-impregnated test strips as the carrier, the borax could be visually detected by the RGB signals of the captured images, with a detection limit of 0.13 mM (27.05 µg mL-1 for Na2B4O7). Combining ion exchange treatment for food samples and sodium periodate oxidation for drug samples, the developed methods were successfully applied for the direct analysis of borax in various products with the recoveries of 86.9-106.3% for traditional fluorescence analysis and 82.7-108.8% for smartphone-assisted fluorescence sensing. The fluorescence property of the morin-borax system was studied using time-dependent density functional theory, and the sensing mechanism was discussed in conjunction with experimental research.
Asunto(s)
Flavonas , Flavonoides , Flavonoles , Papel , Teléfono Inteligente , Espectrometría de Fluorescencia , Flavonoles/análisis , Espectrometría de Fluorescencia/métodos , Flavonoides/análisis , Boratos/química , Límite de Detección , Colorantes Fluorescentes/química , FluorescenciaRESUMEN
In the present work, glass samples in the (100 - x)B2O3-xLi2O binary system, with x varying from 30 to 50 mol%, were prepared using the conventional melting and moulding method, with the main objective of evaluating the thermoluminescence response when exposing these materials to ultraviolet (UV) radiation. Complementary analysis based on density, optical absorption on the UV-visible region (UV-vis absorbance), Fourier transform infrared spectroscopy on the medium region, X-ray diffraction, and differential thermal analysis measurements were performed. Thermoluminescence measurements of vitreous samples showed glow curves with at least one peak with a maximum temperature of ~170°C after exposure to UV radiation in the temperature range 50-250°C. Samples were also exposed to beta radiation in the temperature range 25-275°C, also showing single peaks with a maximum temperature of ~150°C.
Asunto(s)
Partículas beta , Boratos , Boratos/química , Compuestos de Litio , TemperaturaRESUMEN
Glioblastoma multiforme (GBM) is a highly aggressive and lethal form of primary brain tumour. Borax has been demonstrated to exhibit anti-cancer activity through cell death pathways. However, the specific impact of borax on ferroptosis in GBM is not well-established, and the underlying regulatory mechanisms remain unclear. Initially, the effective concentration of borax on cell viability and proliferation in U251 and A172 cells was determined. Subsequently, the effects of borax on the wound healing were analysed. Nuclear factor erythroid 2-related factor 2 (NRF2), glutathione peroxidase 4 (GPx4), glutathione (GSH), HSP70 protein 5 (HSPA5), malondialdehyde (MDA) levels and caspase-3/7 activity were determined in borax-treated and untreated cells. Finally, the protein expression levels of HSPA5, NRF2 and GPx4 were analysed. Borax suppressed cell viability and proliferation in U251 and A172 cells in a concentration- and time-dependent manner. In addition, borax treatment decreased GPx4, GSH, HSPA5 and NRF2 levels in U251 and A172 cells while increasing MDA levels and caspase-3/7 activity. Moreover, borax reduced mRNA and protein levels of HSPA5, NRF2 and GPx4 in U251 and A172 cells. Consequently, borax may induce ferroptosis in GBM cells and regulate the associated regulatory mechanisms targeting NRF2 and HSPA5 pathways. This knowledge may contribute to the development of novel therapeutic approaches targeting ferroptosis in GBM and potentially improve patient outcomes.