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1.
Molecules ; 29(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38792130

RESUMO

Lycium ruthenicum Murray possesses significant applications in both food and medicine, including antioxidative, anti-tumor, anti-fatigue, anti-inflammatory, and various other effects. Consequently, there has been a surge in research endeavors dedicated to exploring its potential benefits, necessitating the organization and synthesis of these findings. This article systematically reviews the extraction and content determination methods of active substances such as polysaccharides, anthocyanins, flavonoids, and polyphenols in LRM in the past five years, as well as some active ingredient composition determination methods, biological activities, and product development. This review is divided into three main parts: extraction and determination methods, their bioactivity, and product development. Building upon prior research, we also delve into the economic and medicinal value of Lycium ruthenicum Murray, thereby contributing significantly to its further exploration and development. It is anticipated that this comprehensive review will serve as a valuable resource for advancing research on Lycium ruthenicum Murray.


Assuntos
Lycium , Extratos Vegetais , Lycium/química , Extratos Vegetais/química , Antocianinas/química , Humanos , Flavonoides/química , Antioxidantes/química , Antioxidantes/farmacologia , Polifenóis/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Polissacarídeos/química
2.
Sensors (Basel) ; 20(3)2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979160

RESUMO

This research demonstrated the development of a simple, cost-effective, and label-free immunosensor for the detection of α-synuclein (α-Syn) based on a cystamine (CYS) self-assembled monolayer (SAM) decorated fluorine-doped tin oxide (FTO) electrode. CYS-SAM was formed onto the FTO electrode by the adsorption of CYS molecules through the head sulfur groups. The free amine (-NH2) groups at the tail of the CYS-SAM enabled the immobilization of anti-α-Syn-antibody, which concurrently allowed the formation of immunocomplex by covalent bonding with α-Syn-antigen. The variation of the concentrations of the attached α-Syn at the immunosensor probe induced the alternation of the current and the charge transfer resistance (Rct) for the redox response of [Fe(CN)6]3-/4-, which displayed a linear dynamic range from 10 to 1000 ng/mL with a low detection limit (S/N = 3) of ca. 3.62 and 1.13 ng/mL in differential pulse voltammetry (DPV) and electrochemical impedance spectra (EIS) measurements, respectively. The immunosensor displayed good reproducibility, anti-interference ability, and good recoveries of α-Syn detection in diluted human serum samples. The proposed immunosensor is a promising platform to detect α-Syn for the early diagnose of Parkinson's disease, which can be extended for the determination of other biologically important biomarkers.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Eletrodos , Cistamina/química , alfa-Sinucleína/análise
3.
Mikrochim Acta ; 187(1): 6, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31797062

RESUMO

A comparative study was carried out on the electrochemical behavior of three carbonized zeolitic imidazolate frameworks (ZIFs) synthesized through solvothermal pyrolysis. An electrochemical sensor for acetaminophen (ACT) was subsequently developed. The sensor was made by coating the glassy carbon electrode (GCE) with cobalt-nitrogen co-doped carbon nanotube hollow polyhedron (Co-NCNHP), which was prepared from core shell ZIF-8@ZIF-67, before electrodeposition of gold nanoparticles. Due to the high specific surface area, good electrical conductivity and stability of both Co-NCNHP and the gold nanoparticles, the resultant sensor displayed excellent electrocatalytic activity towards ACT with the catalytic rate constant Kcat of 4.9 × 105 M-1 s-1, diffusion coefficient D of 1.8 × 10-6 cm2 s-1, high sensitivity of 1.75 µA µM-1 cm-2, and best at a working voltage of 0.35 V (vs. Ag/AgCl). Benefitting from the synergistic effect of both Co-NCNHP and gold nanoparticles, the modified GCE had a linear response in the 0.1 µM-250 µM ACT and detection limit of 0.05 µM (at S/N = 3). The sensor was successfully applied to quantify ACT in tablets and spiked urine samples with recoveries ranged between 96.0% and 105.2%. Graphical abstractSchematic representation of cobalt-nitrogen co-doped carbon nanotube hollow polyhedrons (Co-NCNHP) exhibiting superior electrocatalytic activity to carbonized ZIF-8 and carbonized ZIF-67. Co-NCNHP were coupled to electrodeposition gold nanoparticles to modify glassy carbon electrode for improving acetaminophen (ACT) redox.


Assuntos
Acetaminofen/análise , Galvanoplastia , Ouro/química , Imidazóis/química , Nanopartículas Metálicas/química , Nanotubos de Carbono/química , Zeolitas/química , Acetaminofen/química , Acetaminofen/urina , Catálise , Difusão , Eletroquímica , Eletrodos , Humanos , Concentração de Íons de Hidrogênio , Cinética , Limite de Detecção
4.
Animals (Basel) ; 13(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37835747

RESUMO

Animal viruses are a significant threat to animal health and are easily spread across the globe with the rise of globalization. The limitations in diagnosing and treating animal virus infections have made the transmission of diseases and animal deaths unpredictable. Therefore, early diagnosis of animal virus infections is crucial to prevent the spread of diseases and reduce economic losses. To address the need for rapid diagnosis, electrochemical sensors have emerged as promising tools. Electrochemical methods present numerous benefits, including heightened sensitivity and selectivity, affordability, ease of use, portability, and rapid analysis, making them suitable for real-time virus detection. This paper focuses on the construction of electrochemical biosensors, as well as promising biosensor models, and expounds its advantages in virus detection, which is a promising research direction.

5.
Nanoscale ; 14(3): 890-897, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34985490

RESUMO

The polyethylene oxide (PEO) solid electrolyte is a promising candidate for all solid state lithium-ion batteries (ASSLIBs), but its low ionic conductivity and poor interfacial compatibility against lithium limit the rate and cycling performance of the cell. Herein, the novel and efficient TiO2@polydopamine (PDA) fillers have been synthesized by coating PDA onto the surface of the TiO2 nanofibers, which are then incorporated into PEO matrices to form the composite electrolyte. The composite electrolyte displays a higher ionic conductivity of 4.36 × 10-4 S cm-1, a wider electrochemical window up to about 5 V and a higher tLi+ of 0.190 at 55 °C compared to the PEO electrolyte. Additionally, the Li/composite electrolyte/Li batteries show a stable Li plating/stripping cycle performance, indicating good interfacial compatibility between the composite electrolyte and lithium. Thus, the LiFePO4/Li ASSLIBs display a fantastic rate performance and cycling stability, and deliver superior discharge specific capacities of 153.83 and 136.45 mA h g-1 at current densities of 0.5C and 2C, achieving good capacity retentions of 93.27% and 91.23% at 0.5C and 1C after 150 cycles, respectively. Therefore, the PEO-TiO2@PDA composite electrolyte is a potential solid electrolyte for ASSLIBs.

6.
Nanomaterials (Basel) ; 12(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35889733

RESUMO

Superhydrophobic materials have been widely applied in rapid removal and collection of oils from oil/water mixtures for increasing damage to environment and human beings caused by oil-contaminated wastewater and oil spills. Herein, superhydrophobic materials were fabricated by a novel polypyrrole (PPy)/ZnO coating followed by hexadecyltrimethoxysilane (HDTMS) modification for versatile oil/water separation with high environmental and excellent reusability. The prepared superhydrophobic surfaces exhibited water contact angle (WCA) greater than 150° and SA less than 5°. The superhydrophobic fabric could be applied for separation of heavy oil or light oil/water mixtures and emulsions with the separation efficiencies above 98%. The coated fabric also realized highly efficient separation with harsh environmental solutions, such as acid, alkali, salt, and hot water. The superhydrophobic fabric still remained, even after 80 cycles of separation and 12 months of storage in air, proving excellent durability. These novel superhydrophobic materials have indicated great development potentials for oil/water separation in practical applications.

7.
RSC Adv ; 12(40): 26070-26077, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36275120

RESUMO

Iron (Fe) substitution is an effective strategy for improving the electrochemical performance of LiMnPO4 which has poor conductivity. Herein, we focus on investigating the effect of substitution of Mn with different iron sources, on the structure and electrochemical performances of the LiMnPO4 materials. The Fe-substituted LiMnPO4/C composites were synthesized via a simple and rational solid-state method, and will be of benefit for engineering applications. The characterization of the materials shows an obvious influence of the iron sources on structure and morphology. The N-LMFP material prepared using soluble FeNO3 as iron sources exhibits an excellent rate capacity of 122 mA h g-1 at 5C, and superior cyclability with a capacity retention of 98.9% after 400 cycles at 2C. The enhanced rate capability and cycling stability of N-LMFP are the result of the lowered electron/ion resistance and the improved reversibility of the reaction, that originates from the homogeneous fine particles and hierarchical structure with large mesopores. This research provides significant guidelines for designing an LiMnPO4 cathode with a high performance.

8.
Nanomaterials (Basel) ; 12(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36144908

RESUMO

Intelligent surfaces with controlled wettability have caught much attention in industrial oily wastewater treatment. In this study, a hygro-responsive superhydrophilic/underwater superoleophobic coating was fabricated by the liquid-phase deposition of SiO2 grafted with perfluorooctanoic acid. The wettability of the surface could realize the transformation from superhydrophilicity/underwater superoleophobicity (SHI/USOB) to superhydrophobicity/superoleophilicity (SHB/SOI), both of which exhibited excellent separation performance towards different types of oil-water mixtures with the separation efficiency higher than 99%. Furthermore, the long-chain perfluoroakyl substances on the surface could be decomposed by mixing SiO2 with TiO2 nanoparticles under UV irradiation, which could reduce the pollution to human beings and environment. It is anticipated that the prepared coating with controlled wettability could provide a feasible solution for oil-water separation.

9.
Dalton Trans ; 50(5): 1703-1711, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33443530

RESUMO

Transition metal phosphides are used as anode materials for lithium-ion batteries because of their high theoretical capacity and low polarization. In this work, a core-shell GaP@C nanocomposite was successfully synthesized by a simple chemical vapor deposition (CVD) method, utilizing commercial GaP as the raw material and xylene as the carbon source. The uniform thin carbon shell could alleviate the volumetric variation and improve the conductivity of the inner GaP. When used as an anode in lithium-ion batteries, the GaP@C nanocomposite has a capacity of 812 mA h g-1 at a current density of 0.5 A g-1 after 100 cycles. At a high current density of 2 A g-1, the GaP@C anode delivers a good capacity value of 1087 mA h g-1.

10.
Materials (Basel) ; 13(15)2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32722295

RESUMO

Liquid food adhesion on containers has increased food waste and pollution, which could be effectively alleviated with a superhydrophobic surface. In this research, the superhydrophobic coating was fabricated with edible soybean wax on different substrates by a spraying method. The coated surface showed excellent superhydrophobicity due to its microstructure formed by self-roughening, which could repel a variety of viscous liquid food with the apparent contact angle of 159 ± 2°. The coated surface was still liquid-repellent after hot water immersion (45 °C), abrasion test with sandpaper, water impact, finger touch and immersion into yogurt. The liquid-repellent coating with soybean wax, which is natural and green, is promising for application in the food industry to reduce waste.

11.
Sci Rep ; 10(1): 10607, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32606291

RESUMO

A uric acid (UA) electrochemical biosensor was constructed using ferrocene (Fc) decorated cuprous oxide (Cu2O) enhanced electro-active characteristics and covalently immobilized with uricase (UOx) on glassy carbon electrode (GCE). The electrochemical characteristics of the fabricated electrode was analysed by cyclic voltammetry, electrochemical impedance spectroscopy and differential pulse voltammetry (DPV). DPV studies revealed rapid response of fabricated electrode UOx/Fc/Cu2O/GCE towards UA in a wide concentration range of 0.1-1,000 µM with a sensitivity of 1.900 µA mM-1 cm-2 and very low detection limit of 0.0596 µM. A very low magnitude Michaelis-Menten constant (Km) value was evaluated as 34.7351 µM which indicated the chemical attraction of the enzyme towards the UA was much higher. The developed biosensor was successfully applied to detect UA in human urine samples. Moreover, reproducibility and stability studies demonstrated the fabricated UOx/Fc/Cu2O/GCE biosensor had high reproducibility with a RSD of 2.8% and good reusability with a RSD of 3.2%. Specificity studies results showed the fabricated biosensor had strong anti-interference ability. The improved sensor performance was attributed to the synergistic electronic properties of Cu2O and Fc that provided enhances delectrocatalytic activity and electron transfer. The present biosensor can be extended for use in clinical settings.


Assuntos
Técnicas Biossensoriais/métodos , Eletroquímica/métodos , Ácido Úrico/química , Carbono/química , Cobre/química , Eletrodos , Compostos Ferrosos/química , Metalocenos/química
12.
RSC Adv ; 10(54): 32345-32349, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35516520

RESUMO

A bagasse-based 3D carbon matrix (BC) with high specific surface area and high conductivity was obtained by carbonization and pore-forming processes with bagasse as the carbon precursor and K2FeO4 as the pore-former. The microporous structure and nitrogenous functional groups were determined in the prepared carbon matrix, which could allow high sulfur loading and improve the polysulfide absorption capacity during cycling. After sulfur infusion, the S/BC composite with 68.8% sulfur content was obtained. The lithium-sulfur (Li-S) battery with the S/BC cathode shows high specific capacity and good cycling performance. It delivers a specific capacity of 1360 mA h g-1 at 0.2C and remains at 790 mA h g-1 after 200 cycles. At 1C, the Li-S with this composite cathode exhibits 601 mA h g-1 after 150 cycles. This work offers a new kind of green material and a new method for Li-S batteries.

13.
Materials (Basel) ; 12(20)2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31635196

RESUMO

In this paper, a novel superhydrophobic magnetic sawdust (SMSD) was fabricated as an oil sorbent. The SMSD was functionalized with Fe3O4 nanoparticles using melamine formaldehyde resin (MFR) as a coupling agent and subsequently hydrophobically-treated with hexadecyltrimethoxysilane (HDTMS). The SMSD showed excellent superhydrophobicity with the water contact angle of 155.3 ± 0.9°. Meanwhile it had remarkable environmental durability, long-term stability, and mechanical durable properties. Taking advantage of its magnetic characteristics, the SMSD could be easily controlled to absorb oil to separate oil-water mixtures with high oil absorption capacity and good reusability. Moreover, the emulsion was successfully separated by SMSD, including water-in-oil and oil-in-water emulsions. This study developed an effective oil absorbent, which was low cost and environmentally-friendly.

14.
Sci Rep ; 9(1): 9823, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31285508

RESUMO

Based on the structural characteristics of the anodes of lithium-ion batteries, an improved Hummers' method is proposed to recycle the anode materials of spent lithium-ion batteries into graphene. In order to effectively separate the active material from the copper foil, water was selected as an ultrasonic solvent in this experiment. In order to further verify whether lithium ions exist in the active material, carbon powder, it was digested by microwave digestion. ICP-AES was then used to analyse the solution. It was found that lithium ions were almost non-existent in the carbon powder. In order to further increase the added value of the active material, graphene oxide was obtained by an improved Hummers' method using the carbon powder. The graphene material was also reduced by adding vitamin C as a reducing agent through a chemical reduction method using graphene oxide. Meanwhile, the negative graphite, graphite oxide and graphene samples were characterized by XRD, SEM, FTIR and TEM. The conductivity of the negative graphite, graphite oxide and graphene was tested. The results show that graphene prepared by a redox method has a better layered structure, less impurities and oxygen groups in its molecular structure, wider interlayer spacing and smaller resistivity.

15.
Bioelectrochemistry ; 72(1): 87-93, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18155968

RESUMO

Electrodes for the dopamine (DA) determination in biological samples have been developed with improved selectivity and sensitivity in an excess of ascorbic acid (AA). Negatively charged Ni(II) complex was synthesized and electropolymerized on the glassy carbon electrode to impart the surface with anionic characteristics that could act both as a catalyst and as a discriminating layer against AA based on the electrostatic interaction. Thus prepared electrodes enabled selective determination of DA even in a large excess of AA by differential pulse voltammetry at physiological pH. Linear response was found down to 1.0 x 10(-7) M with 5.0 x 10(-9) M of LOD (Limit of Detection). In a flow injection analysis performed in an amperometric mode, the detection limit was lowered by two orders of magnitude down to 1.0 x 10(-9) M with a linear range of 1.0 x 10(-9) to 1.0 x 10(-6) M. The relative standard deviation was found to be 3.36% from 25 independent measurements for 1.0 x 10(-5) M of DA. Stable oxidation current of DA was observed even after 30 days storage in air. The recoveries of DA in the 100-fold diluted human urine samples were 97.7% for 4 measurements. The rate constant for the DA oxidation was 1.3 x 10(-3) cm s(-1) from hydrodynamic experiments using a rotating disk electrode.


Assuntos
Ácido Ascórbico/análise , Dopamina/análise , Dopamina/química , Níquel/química , Polímeros/química , Ácido Ascórbico/química , Calibragem , Catálise , Eletrodos , Humanos , Concentração de Íons de Hidrogênio , Cinética , Compostos Macrocíclicos/química , Oxirredução , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Eletricidade Estática
16.
Chem Commun (Camb) ; 54(100): 14093-14096, 2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30488908

RESUMO

An in situ chemically and physically confined sulfur-polymer composite (denoted as SPANI) is synthesized by sulfurizing PANI through a one-step thermal treatment. The SPANI cathode exhibits excellent cycling stability in commercial carbonate-based electrolytes. It offers a new insight into sulfur cathode design for high performance Li-S batteries.

17.
RSC Adv ; 8(57): 32740-32746, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-35547678

RESUMO

Herein, we fabricated a sensitive rutin electrochemical sensor via modifying glassy carbon electrode (GCE) with zeolitic imidazolate framework-8 (ZIF-8) and acetylene black (AB) in the presence of chitosan (CS). The electrochemical activity and experimental parameters of the ZIF-8-AB-CS/GCE sensor were investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimal conditions, the sensor presented a reasonable linear response in the range of 0.1-10 µM with a limit of detection (LOD) as low as 0.004 µM (S/N = 3). The sensor possessed good reproducibility and high stability, and was successfully applied to detect rutin tablet samples with satisfactory results, which was attributed to the synergistic effect between ZIF-8 and AB. Meanwhile, the sensor displayed a potential application for detection of other analytes in real samples. Furthermore, a probable interaction mechanism was proposed to account for the interaction between rutin and the nanocomposite electrode, which was not discussed in previous reports.

18.
J Food Drug Anal ; 22(3): 345-349, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28911424

RESUMO

A simple and sensitive electrochemical method for the simultaneous and quantitative detection of ranitidine (RT) and metronidazole (MT) was developed, based on a poly(chromotrope 2B) modified activated glassy carbon electrode (PCHAGCE). The PCHAGCE showed excellent electrocatalytic activity toward the reduction of both RT and MT in 0.1 mol/L phosphate buffer solution (pH 6.0). The peak-to-peak separations for the simultaneous detection of RT and MT between the two reduction waves in cyclic voltammetry were increased significantly from ∼0.1 V at activated GCE, to ∼0.55 V at PCHAGCE. By differential pulse voltammetry techniques, the reduction peak currents of RT and MT were both linear over the range of 1.0 × 10-5-4.0×10-4 mol/L. The detection limits (S/N = 3) were 5.4 × 10-7 mol/L and 3.3 × 10-7 mol/L for RT and MT, respectively. The modified electrode was successfully applied to the determination of RT and MT in pharmaceutical preparations and human serum as real samples with stable and reliable recovery data.

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