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1.
J Am Chem Soc ; 146(25): 17517-17529, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38869959

RESUMEN

Despite the widespread use of hydrophilic building blocks to incorporate 18F and improve tracer pharmacokinetics, achieving effective leaving group-mediated nucleophilic 18F-fluorination in water (excluding 18F/19F-exchange) remains a formidable challenge. Here, we present a water-compatible SN2 leaving group-mediated 18F-fluorination method employing preconjugated "AquaF" (phosphonamidic fluorides) building blocks. Among 19 compact tetracoordinated pentavalent P(V)-F candidates, the "AquaF" building blocks exhibit superior water solubility, sufficient capacity for 18F-fluorination in water, and excellent in vivo metabolic properties. Two nitropyridinol leaving groups, identified from a pool of leaving group candidates that further enhance the precursor water solubility, enable 18F-fluorination in water with a 10-2 M-1 s-1 level reaction rate constant (surpassing the 18F/19F-exchange) at room temperature. With the exergonic concerted SN2 18F-fluorination mechanism confirmed, this 18F-fluorination method achieves ∼90% radiochemical conversions and reaches a molar activity of 175 ± 40 GBq/µmol (using 12.2 GBq initial activity) in saline for 12 "AquaF"-modified proof-of-concept functional substrates and small-molecule 18F-tracers. [18F]AquaF-Flurpiridaz demonstrates significantly improved radiochemical yield and molar activity compared to 18F-Flurpiridaz, alongside enhanced cardiac uptake and heart/liver ratio in targeted myocardial perfusion imaging, providing a comprehensive illustration of "AquaF" building blocks-assisted water-compatible SN2 18F-fluorination of small-molecule radiotracers.


Asunto(s)
Radioisótopos de Flúor , Halogenación , Agua , Radioisótopos de Flúor/química , Agua/química , Animales , Radiofármacos/química , Radiofármacos/síntesis química , Ratones , Tomografía de Emisión de Positrones , Solubilidad , Estructura Molecular , Trazadores Radiactivos
2.
Small ; 20(13): e2309154, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37967335

RESUMEN

Aqueous batteries have garnered significant attention in recent years as a viable alternative to lithium-ion batteries for energy storage, owing to their inherent safety, cost-effectiveness, and environmental sustainability. This study offers a comprehensive review of recent advancements, persistent challenges, and the prospects of aqueous batteries, with a primary focus on energy density compensation of various battery engineering technologies. Additionally, cutting-edge high-energy aqueous battery designs are emphasized as a reference for future endeavors in the pursuit of high-energy storage solutions. Finally, a dual-compatibility battery configuration perspective aimed at concurrently optimizing cycle stability, redox potential, capacity utilization for both anode and cathode materials, as well as the selection of potential electrode candidates, is proposed with the ultimate goal of achieving cell-level energy densities exceeding 400 Wh kg-1.

3.
Small ; : e2401857, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38676350

RESUMEN

The performance of electrochemical batteries is intricately tied to the physicochemical environments established by their employed electrolytes. Traditional battery designs utilizing a single electrolyte often impose identical anodic and cathodic redox conditions, limiting the ability to optimize redox environments for both anode and cathode materials. Consequently, advancements in electrolyte technologies are pivotal for addressing these challenges and fostering the development of next-generation high-performance electrochemical batteries. This review categorizes perspectives on electrolyte technology into three key areas: additives engineering, comprehensive component analysis encompassing solvents and solutes, and the effects of concentration. By summarizing significant studies, the efficacy of electrolyte engineering is highlighted, and the review advocates for further exploration of optimized component combinations. This review primarily focuses on liquid electrolyte technologies, briefly touching upon solid-state electrolytes due to the former greater vulnerability to electrode and electrolyte interfacial effects. The ultimate goal is to generate increased awareness within the battery community regarding the holistic improvement of battery components through optimized combinations.

4.
Chemistry ; 30(27): e202400584, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38451164

RESUMEN

Solid polymer electrolytes (SPEs) have garnered extensive attention as potential alternatives to traditional liquid electrolytes, primarily due to their prowess in curbing lithium dendrite formation and preventing electrolyte leaks. The quest for SPEs that are both mechanically robust and exhibit superior ionic conductivity has been vigorous. However, achieving a harmonious balance between these two attributes remains a significant challenge. In this study, we introduce a novel quasi-solid electrolyte, ingeniously crafted from a poly(urethane-urea) network, enriched with lithium salts and plasticizers. This innovative composition not only boasts remarkable toughness but also ensures commendable ionic conductivity. Our post-gelation method yields gel polymer electrolytes that undergo rigorous evaluation, leading to an optimized version that stands out with its exceptional room-temperature ionic conductivity (2.94×10-4 S cm-1) and outstanding toughness (11.9 MJ m-3). Moreover, it demonstrates a broad electrochemical window (4.73 V), remarkable stability across a 600-hour cycle test, a high capacity retention exceeding 80 % after 100 cycles at 0.2 C, and a noteworthy self-healing capability. This quasi-solid polymer electrolyte emerges as a promising contender to replace current liquid electrolyte solutions.

5.
Gen Comp Endocrinol ; 347: 114426, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38103843

RESUMEN

Fibroblast growth factors (FGFs) are a family of structurally related peptides that regulate processes such as cell proliferation, differentiation, and damage repair. In our previous study, fibroblast growth factor receptor 4 (fgfr4) was detected in the most significant quantitative trait loci (QTL), when identified of QTLs and genetic markers for growth-related traits in spotted sea bass. However, knowledge of the function of fgfr4 is lacking, even the legends to activate the receptor is unknown in fish. To remedy this problem, in the present study, a total of 33 fgfs were identified from the genomic and transcriptomic databases of spotted sea bass, of which 10 were expressed in the myoblasts. According to the expression pattern during myoblasts proliferation and differentiation, fgf6a, fgf6b and fgf18 were selected for further prokaryotic expression and purification. The recombinant proteins FGF6a, FGF6b and FGF18 were found to inhibit myoblast differentiation. Overall, our results provide a theoretical basis for the molecular mechanisms of growth regulation in economic fish such as spotted sea bass.


Asunto(s)
Lubina , Animales , Lubina/genética , Transcriptoma , Perfilación de la Expresión Génica , Genómica , Factores de Crecimiento de Fibroblastos/genética
6.
Small ; : e2309231, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38059870

RESUMEN

The capacity to self-detect and locate damage to underwater infrastructure in emergencies is vital, as materials and technologies that securely facilitate energy and information transmission are crucial in several fields. Herein, the development of a multifunctional supramolecular ionogel (SIG) and SIG-based devices for use in detecting and locating damage to underwater infrastructure is reported. The SIG is fabricated via the single-step photoinitiated copolymerization of hydroxy and fluorinated monomers in a fluorinated ionic liquid. Hydrogen-bond/ion-dipole-interaction synergy ensures that the SIG is highly ionically conductive and extremely mechanically strong, with underwater self-healing and adhesion properties. It can be used as an underwater ionic cable to provide reporting signals via changes in strain; furthermore, SIG-based devices can be fixed to underwater infrastructure to locate damage via resistance monitoring. The SIG can also be attached to the human body for use in underwater communication, thereby safeguarding maintenance personnel while repairing underwater infrastructure. This study provides a novel pathway for developing supramolecular materials and devices.

7.
Small ; 19(39): e2302650, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37264736

RESUMEN

Metallic zinc (Zn) is a highly promising anode material for aqueous energy storage systems due to its low redox potential, high theoretical capacity, and low cost. However, rampant dendrites/by-products and torpid Zn2+ transfer kinetics at electrode/electrolyte interface severely threaten the cycling stability, which deteriorate the electrochemical performance of Zn-ion batteries. Herein, an interfacial engineering strategy to construct alkaline earth fluoride modified metal Zn electrodes with long lifespan and high capacity retention is reported. The compact fluoride layer is revealed to guide uniform Zn stripping/plating and accelerate the transfer/diffusion of Zn2+ via Maxwell-Wagner polarization. A series of in situ and ex situ spectroscopic studies verified that the fluoride layer can guide uniform Zn stripping/plating. Electrochemical kinetics analyses reveal that positive effect on the removal of Zn2+ solvation sheath provided by fluoride layer. Meanwhile, this fluoride coating layer can act as a barrier between the Zn electrode and electrolyte, providing a high electrode overpotential toward hydrogen evolution reaction to hold back H2 evolution. Consequently, the fluoride-modified Zn anode exhibited a capacity retention of 88.2% after 4000 cycles under10 A g-1 . This work opens up a new path to interface engineering for propelling the exploration of advanced rechargeable aqueous Zn-ion batteries.

8.
Chemistry ; 29(37): e202300248, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37102671

RESUMEN

18 F-Labeled molecular tracers and subsequent positron emission tomography are indispensable molecular imaging tools in medical diagnosis and research. The preparation of 18 F-labeled molecular tracers involves critical steps such as the 18 F-labeling reaction, work-up, and 18 F-product purification, which are governed by 18 F-labeling chemistry. Since direct incorporation of 18 F in aqueous media exhibits many advantages in practice, this Review summarizes the existing 18 F-labeling methods in aqueous media, which are sorted by atoms forming chemical covalent bonds with F. The Review is focused on the respective reaction mechanism, the water effect and the applications of these methods for the development of 18 F-radiopharmaceuticals. The research progress on aqueous nucleophilic labeling methods using [18 F]F- as the 18 F source has been mainly discussed.

9.
BMC Oral Health ; 23(1): 242, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-37101257

RESUMEN

BACKGROUND: Visual or hearing impairments in students seriously affect their quality of life. The aim of this study was to identify oral hygiene status and its influencing factors on visual or hearing impairments in students in Northeast China. METHODS: This study was conducted in May 2022. A total of 118 visually impaired students and 56 hearing impaired students from Northeast China were included in this study via census. Oral examinations and questionnaire-based surveys of students and their teachers were conducted. The oral examinations included caries experience, prevalence of gingival bleeding and dental calculus. The questionnaires included three parts: Social demographics (residence, sex and race) and parents' educational level; Oral hygiene habits and medical treatment behaviors; Knowledge and attitudes towards oral health care. This questionnaire was selected from the Fourth China National Oral Health Survey and the reliability and validity of the questionnaire were previously tested. T tests, one-way ANOVA, χ2 tests and multivariate logistic analyses were conducted to evaluate the differences and dependent variables of dental caries. RESULTS: The prevalence of dental caries in visually impaired and hearing impaired students were 66.10% and 66.07%. The mean number of DMFT, prevalence of gingival bleeding and dental calculus in visually impaired students were 2.71 ± 3.06, 52.08% and 59.38%, respectively. The mean number of DMFT, prevalence of gingival bleeding and dental calculus in hearing impaired students were 2.57 ± 2.83, 17.86% and 42.86%, respectively. The results of the multivariate logistic analysis showed that fluoride use and parents' educational background had an impact on the caries experience of visually impaired students. The daily toothbrushing frequency and parents' educational background had an impact on the caries experience of hearing impaired students. CONCLUSIONS: The oral health situation of students with visual or hearing impairments remains severe. It is still necessary to promote oral and general health in this population.


Asunto(s)
Caries Dental , Pérdida Auditiva , Humanos , Salud Bucal , Caries Dental/epidemiología , Calidad de Vida , Cálculos Dentales , Reproducibilidad de los Resultados , Estudiantes , Pérdida Auditiva/epidemiología , China/epidemiología , Prevalencia , Índice CPO , Estado de Salud
10.
BMC Oral Health ; 23(1): 809, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891599

RESUMEN

BACKGROUND: Children aged 6-9 years are vulnerable to dental caries due to age-related limitations and a lack of adequate knowledge regarding oral health and hygiene practices. This study aimed to establish a cohort of children aged between 6 and 9 years and conducted a 12-month follow-up to examine the combined effect of pit and fissure sealant (PFS) application and oral health education on their oral health status. METHODS: A cohort study with 12-month follow-up was conducted in Liaoning province, China. A multi-stage stratified cluster sampling approach was employed in the study. The enrolled 6- to 9-year-old children were all from the selected primary schools, who had resided in the designated area for at least 6 months. Children who were unable to cooperate with the examiner or without informed consent from their guardians were excluded. Experienced dental professionals examined the oral health status of primary school children aged 6-9 years. All children and their guardians were mandated to complete a questionnaire (qualitative data) at the beginning of the study. In the experiment group, children underwent PFS application and chairside oral health education. Clinical examinations and questionnaire surveys were repeated at the 12-month follow-up. The chi-square test and binary logistic regression were conducted to investigate the potential risk factors associated with dental caries prevalence (dependent variable). Independent variables were items from the questionnaire (such as living place, parents' education level and children' birth weight). The significant variables identified in the chi-square tests were subsequently included in the binary logistic regression analysis. RESULTS: A total of 4,085 children aged 6-9 years were included in the study, with 1805 participants assigned to the experiment group and 2280 to the control group. At baseline, the caries rates of the experimental and control group were 77.95% and 80.35%, respectively without any statistically significant differences. However, at the 12-month follow-up, the caries rate in the experimental group (83.65%) was significantly lower than that in the control group (86.62%) (P < 0.05). The results from the binary logistic regression analysis indicated that parents with a college degree and children in the experimental group exhibited lower caries rates. Conversely, higher caries rates were associated with the consumption of sweet beverages and foods more than once a day and a lack of knowledge regarding the causes of caries (P < 0.05). CONCLUSIONS: In Liaoning, China, children aged 6 to 9 years exhibited a high prevalence of dental caries. Several factors, including the parent's education level, the frequency of consuming sweet beverages and foods, and the children's understanding of the cause of caries, significantly affected the caries prevalence rates. The implementation of PFS application and oral health education effectively reduce the caries rate among the surveyed children.


Asunto(s)
Caries Dental , Salud Bucal , Humanos , Niño , Lactante , Caries Dental/epidemiología , Caries Dental/prevención & control , Estudios de Seguimiento , Selladores de Fosas y Fisuras/uso terapéutico , Estudios de Cohortes , Educación en Salud Dental , China/epidemiología
11.
Angew Chem Int Ed Engl ; 62(29): e202301762, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37208825

RESUMEN

Supramolecular interactions facilitate the development of tough multifunctional thermoplastic elastomers. However, the fundamental principles that govern supramolecular toughening are barely understood, and the rational design to achieve the desired high toughness remains daunting. Herein, we report a simple and robust method for toughening thermoplastic elastomers by rationally tailoring hard-soft phase separation structures containing rigid and flexible supramolecular segments. The introduced functional segments with distinct structural rigidities provide mismatched supramolecular interactions to efficiently tune the energy dissipation and bear an external load. The optimal supramolecular elastomer containing aromatic amide and acylsemicarbazide moieties demonstrates a record toughness (1.2 GJ m-3 ), extraordinary crack tolerance (fracture energy 282.5 kJ m-2 ), an ultrahigh true stress at break (2.3 GPa), good elasticity, healing ability, recyclability, and impact resistance. The toughening mechanism is validated by testing various elastomers, confirming the potential for designing and developing super-tough supramolecular materials with promising applications in aerospace and electronics.

12.
Langmuir ; 38(49): 15433-15441, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36459698

RESUMEN

Most soft actuators have the ability of monotonic responsiveness. That is, there is only one response action after being stimulated once. In this work, a temporarily responsive bilayer hydrogel actuator is designed and fabricated by combining a tertiary amine-containing pH-responsive layer and a urease-containing non-responsive layer. The hydrogel actuator can achieve programed deformation and recovery driven by chemical fuels (i.e., acidic urea solutions), which is essentially regulated by rapid acidification and slow enzymatic production of ammonia for recovering the pH of the system. The actuation extent and duration can be simply controlled by the fuel levels, and the repeated actuations are also possible via refueling. Furthermore, we fabricate several hydrogel devices that can display specific patterns or lift an item. This enzymatic method shows new possibilities to control the temporary actuation of polymer hydrogels potentially useful in many fields such as soft robotics, biomimetic devices, and environmental sensing.


Asunto(s)
Materiales Biomiméticos , Hidrogeles , Polímeros
13.
Langmuir ; 38(1): 514-522, 2022 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-34932363

RESUMEN

Understanding and manipulating wettability alterations has tremendous implications in theoretical research and industrial applications. This study proposes a novel idea of applying ultrasonic for wettability alterations and also provides its quantitative characterizations and in-depth analyses. More specifically, with pretreatment of ultrasonic, mechanisms of wettability alteration were characterized from the contact angle measurements, as well as the in-depth analyses from atomic force microscopy (AFM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). After ultrasonic treatments, the wettability of mineral with low permeability is determined to altered from strong hydrophilic to intermediate wettability. The mechanism interpretations are conducted by means of the AFM, XRD, and FTIR. Basically, as the time of ultrasonic treatment increases, the AFM results indicate that the roughness of rock surface and oil/rock interface (contact area) with surroundings of brine is enhanced. Meanwhile, the XRD results show the diffusions of clays from the rock surface to the aqueous phase, and FTIR indicates that the number of functional groups of Si-O-Si, C-O-C, C-O, C═O, and OH decreases while the number of COOH and C═C═O groups increases. This study clearly reveals the surface chemistry of oil-rock wettability alteration in the subsurface conditions, which would provide technical support for subsurface usage of geo-energy productions and carbon sequestrations.

14.
Nano Lett ; 21(20): 8824-8830, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34617756

RESUMEN

Solar-powered CO2 conversion represents a promising green and sustainable approach for achieving a carbon-neutral economy. However, the rational design of a wide-spectrum sunlight-driven catalysis system for effective CO2 reduction is an ongoing challenge. Herein, we report the preparation of a rhodium/aluminum (Rh/Al) nanoantenna photothermal catalyst that can utilize a broad range of sunlight (from ultraviolet to the near-infrared region) for highly efficient CO2 methanation, achieving a high CH4 selectivity of nearly 100% and an unprecedented CH4 productivity of 550 mmol·g-1·h-1 under concentrated simulated solar irradiation (11.3 W·cm-2). Detailed control experiment results verified that the CO2 methanation process was facilitated by the localized surface plasmonic resonance and nanoantenna effects of the Rh/Al nanostructure under light irradiation. In operando temperature-programmed Fourier transform infrared spectroscopy confirmed that CO2 methanation on the Rh/Al nanoantenna catalyst was a multistep reaction with CO as a key intermediate. The design of a wide-spectrum solar-driven photothermal catalyst provides a feasible strategy for boosting CO2-to-fuel conversion.

15.
Int J Mol Sci ; 23(17)2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36077203

RESUMEN

Temperature strongly modulates muscle development and growth in ectothermic teleosts; however, the underlying mechanisms remain largely unknown. In this study, primary cultures of skeletal muscle cells of Lateolabrax maculatus were conducted and reared at different temperatures (21, 25, and 28 °C) in both the proliferation and differentiation stages. CCK-8, EdU, wound scratch and nuclear fusion index assays revealed that the proliferation, myogenic differentiation, and migration processes of skeletal muscle cells were significantly accelerated as the temperature raises. Based on the GO, GSEA, and WGCNA, higher temperature (28 °C) induced genes involved in HSF1 activation, DNA replication, and ECM organization processes at the proliferation stage, as well as HSF1 activation, calcium activity regulation, myogenic differentiation, and myoblast fusion, and sarcomere assembly processes at the differentiation stage. In contrast, lower temperature (21 °C) increased the expression levels of genes associated with DNA damage, DNA repair and apoptosis processes at the proliferation stage, and cytokine signaling and neutrophil degranulation processes at the differentiation stage. Additionally, we screened several hub genes regulating myogenesis processes. Our results could facilitate the understanding of the regulatory mechanism of temperature on fish skeletal muscle growth and further contribute to utilizing rational management strategies and promoting organism growth and development.


Asunto(s)
Fibras Musculares Esqueléticas , Músculo Esquelético , Animales , Diferenciación Celular/genética , Proliferación Celular/fisiología , Desarrollo de Músculos/genética , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Temperatura
16.
Int J Cosmet Sci ; 44(2): 177-188, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35211990

RESUMEN

OBJECTIVE: Diglucosyl gallic acid is a whitening active with powerful whitening function. When it acts on human skin, microorganisms on the skin surface and part of the stratum corneum produce α-glucosidase to sever the glucose bond of diglucosyl gallic acid, thereby converting part of diglucosyl gallic acid into gallic acid, acting on the skin and exerting the excellent effects of diglucosyl gallic acid and gallic acid at the same time. Diglucosyl gallic acid has high stability and water solubility, it can reduce free radical generation, inhibit tyrosinase generation, prevent melanin transfer, and control skin inflammation. The present study investigates the in vitro tyrosinase inhibition activity, antioxidant capacity of diglucosyl gallic acid as well as its clinical efficacy as a cosmetic ingredient. METHODS: Taking VC and gallic acid as controls, the pH = 6.8, 0.05 mmol/L Na2HPO4-NaH2PO4 buffer solution was prepared to test the tyrosinase inhibitory activity and antioxidant capacity of diglucosyl gallic acid respectively. Using arbutin and nicotinamide, two common cosmetic raw materials as controls, 20 volunteers (aged 20-35 years old) were selected for the test. (2 ± 0.1) mg/cm2 take the lotion to be tested and apply it to the test part evenly, twice a day, volunteers are not allowed to use sunscreen or other sunscreen products during the study period. RESULTS: The results show that diglucosyl gallic acid has a stronger ability to inhibit the activity of tyrosinase compared with VC, and its IC50 value is 2.68 mg/ mL. Their potential antioxidant activities are further evaluated by the DPPH (α, α-diphenyl-ß-picrylhydrazyl) method and the ABTS [2,2´-azinobis-(3-ethylbenz othiazoline-6-sulphonate)] radical cation (ABTS+) method, in which the gallic acid demonstrates a better performance than the traditional antioxidant vitamin C (VC), while the diglucosyl gallic acid shows poorer performance. As to the reducing ability, VC has the best performance, much better than gallic acid and diglucosyl gallic acid. Furthermore, through clinical experiments, it is shown the application of the diglucosyl gallic acid as a cosmetic ingredient can considerably improve the brightness of the skin and meanwhile reduce the area of ultraviolet spots, melanin and erythema over time. CONCLUSION: The above in vitro and in vivo studies on diglucosyl gallic provide the basis for its future application development in cosmetics.


OBJECTIF: L'acide diglucosyl gallique est un actif blanchissant doté d'une puissante fonction blanchissante. Lorsqu'il agit sur la peau humaine, les microorganismes à la surface de la peau et une partie de la couche cornée produisent de l'α-glucosidase pour rompre la liaison glucose de l'acide diglucosyl gallique, convertissant ainsi une partie de l'acide diglucosyl gallique en acide gallique, agissant sur la peau et exerçant les excellents effets de l'acide diglucosyl gallique et de l'acide gallique en même temps. L'acide diglucosyl gallique a une stabilité et une solubilité dans l'eau élevées, il peut réduire la génération de radicaux libres, inhiber la génération de tyrosinase, empêcher le transfert de mélanine et contrôler l'inflammation cutanée. La présente étude examine l'activité d'inhibition de la tyrosinase in vitro, la capacité antioxydante de l'acide diglucosyl gallique ainsi que son efficacité clinique en tant qu'ingrédient cosmétique. MÉTHODE: En prenant VC (vitamine C) et l'acide gallique comme témoins, la solution tampon pH = 6,8, 0,05 mmol / L Na2HPO4-NaH2PO4 a été préparée pour tester respectivement l'activité inhibitrice de la tyrosinase et la capacité antioxydante de l'acide diglucosyl gallique. En utilisant l'arbutine et le nicotinamide, deux matières premières cosmétiques courantes comme témoins, 20 volontaires (âgés de 20 à 35 ans) ont été sélectionnés pour le test. Prendre la lotion à tester et l'appliquer (2 ± 0,1) mg/cm2 uniformément sur la partie testée, deux fois par jour, les volontaires ne sont pas autorisés à utiliser de crème solaire ou d'autres produits de protection solaire pendant la période d'étude. RÉSULTATS: Les résultats montrent que l'acide diglucosyl gallique a une capacité plus forte à inhiber l'activité de la tyrosinase par rapport au VC, et sa valeur IC50 est de 2,68 mg/mL. Leurs activités antioxydantes potentielles sont ensuite évaluées par la méthode DPPH (α, α-diphényl-ß-picrylhydrazyl) et la méthode ABTS [2,2´-azinobis-(3-ethylbenzothiazoline-6-sulfonate)] radical cation (ABTS+), dans laquelle l'acide gallique présente de meilleures performances que la vitamine C (VC) antioxydante traditionnelle, tandis que l'acide diglucosyl gallique présente de moins bonnes performances. Quant au pouvoir réducteur, la VC a les meilleures performances, bien meilleures que l'acide gallique et l'acide diglucosyl gallique. De plus, à travers des expériences cliniques, il est démontré que l'application de l'acide diglucosyl gallique en tant qu'ingrédient cosmétique peut considérablement améliorer la luminosité de la peau et réduire en même temps la surface des taches de soleil, de la mélanine et de l'érythème au fil du temps. CONCLUSION: Les études in vitro et in vivo ci-dessus sur le diglucosyl gallique constituent la base de son futur développement d'applications en cosmétique.


Asunto(s)
Antioxidantes , Cosméticos , Adulto , Antioxidantes/química , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Emulsiones , Ácido Gálico/farmacología , Humanos , Melaninas , Monofenol Monooxigenasa , Protectores Solares , Adulto Joven
17.
Sensors (Basel) ; 20(11)2020 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-32521629

RESUMEN

The notable toxicological impacts of aflatoxin B1 (AFB1) and its main metabolite, aflatoxin M1 (AFM1), on human being health make the evaluation of food quality highly significant. Due to the toxicity of those metabolites-even very low content in foodstuffs-it is crucial to design a sensitive and reliable procedure for their detection. Electrochemical aptamer-based biosensors are considered the most encouraging option, based on multi-placed analysis, rapid response, high sensitivity and specificity. The present review specifically emphasizes the potential utilization of the electrochemical aptasensors for determining the AFM1 and AFB1 with different electrodes.


Asunto(s)
Aflatoxina B1/análisis , Aflatoxina M1/análisis , Aptámeros de Nucleótidos , Técnicas Biosensibles , Técnicas Electroquímicas , Análisis de los Alimentos/métodos
18.
Sensors (Basel) ; 20(13)2020 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-32630056

RESUMEN

Venlafaxine (VEN), as one of the popular anti-depressants, is widely utilized for the treatment of major depressive disorder, panic disorder, as well as anxiety. This drug influences the chemicals in the brain, which may result in imbalance in depressed individuals. However, venlafaxine and its metabolites are contaminants in water. They have exerted an adverse influence on living organisms through their migration and transformation in various forms of adsorption, photolysis, hydrolysis, and biodegradation followed by the formation of various active compounds in the environment. Hence, it is crucial to determine VEN with low concentrations in high sensitivity, specificity, and reproducibility. Some analytical techniques have been practically designed to quantify VEN. However, electroanalytical procedures have been of interest due to the superior advantages in comparison to conventional techniques, because such methods feature rapidity, simplicity, sensitivity, and affordability. Therefore, this mini-review aims to present the electrochemical determination of VEN with diverse electrodes, such as carbon paste electrodes, glassy carbon electrodes, mercury-based electrodes, screen-printed electrodes, pencil graphite electrodes, and ion-selective electrodes.


Asunto(s)
Antidepresivos/análisis , Técnicas Electroquímicas , Clorhidrato de Venlafaxina/análisis , Contaminantes Químicos del Agua/análisis , Carbono , Electrodos , Grafito , Reproducibilidad de los Resultados
19.
Sensors (Basel) ; 20(12)2020 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-32545829

RESUMEN

In recent years, several studies have focused on environmental pollutants. Bisphenol A (BPA) is one prominent industrial raw material, and its extensive utilization and release into the environment constitute an environmental hazard. BPA is considered as to be an endocrine disruptor which mimics hormones, and has a direct relationship to the development and growth of animal and human reproductive systems. Moreover, intensive exposure to the compound is related to prostate and breast cancer, infertility, obesity, and diabetes. Hence, accurate and reliable determination techniques are crucial for preventing human exposure to BPA. Experts in the field have published general electrochemical procedures for detecting BPA. The present timely review critically evaluates diverse chemically modified electrodes using various substances that have been reported in numerous studies in the recent decade for use in electrochemical sensors and biosensors to detect BPA. Additionally, the essential contributions of these substances for the design of electrochemical sensors are presented. It has been predicted that chemically modified electrode-based sensing systems will be possible options for the monitoring of detrimental pollutants.


Asunto(s)
Compuestos de Bencidrilo/análisis , Técnicas Biosensibles , Técnicas Electroquímicas , Contaminantes Ambientales/análisis , Fenoles/análisis , Electrodos
20.
Langmuir ; 35(27): 8943-8949, 2019 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-31244243

RESUMEN

A rapid and accurate determination of interfacial tensions (IFTs) in nanopores is scientifically and practically significant, while most existing experimental measurements are restricted to the micrometer scale and theoretical calculations are relatively limited. In this study, six series of the IFT measurement tests for the binary CO2-C10, C1-C10, and N2-C10 mixtures are conducted at temperatures ( T) of 25.0 and 53.0 °C in a self-manufactured nanofluidic system. Moreover, a nanoscale-extended equation-of-state model considering the effects of the confinement, intermolecular interactions, and disjoining pressure and a semianalytical correlation are proposed to calculate the IFTs of the three mixtures in bulk phase and nanopores. Third, a new Tolman length formulation is developed for the IFT corrections in nanopores. Overall, the calculated IFTs from the two theoretical methods agree well with the measured results for most cases in nanopores. On the other hand, effects of the pore scale, temperature, pressure, and fluid composition on the IFTs of the three mixtures are effectively validated and specifically investigated. One suggestion comes from this work that the two theoretical methods for calculating the IFTs are better to be applied concurrently to minimize errors. Another important future work is to include more pore surface parameter (e.g., wettability) into the theoretical model.

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