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1.
Int J Biol Macromol ; 232: 123344, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36682654

RESUMO

Metal sulfides with the nature of low electronegativity and high electrochemical activity are potentially considered effective electrode materials for supercapacitors. Meanwhile, hierarchical porous carbon (HPC) materials derived from eco-friendly enzymatic hydrolysis lignin are the ideal matrix for holding nanoparticles (NP) that allows the overall NP/HPC composite to achieve outstanding electrochemical performance. In this study, NiCo2S4 nanoparticles were in-situ synthesized on the inner surface of 3D HPC that derived from enzymatic hydrolysis lignin with a simple one-step solvothermal method, thus forming a high-performance composite electrode material for supercapacitor applications. As a result, the NiCo2S4/HPC composite yields an outstanding specific capacity of 1264.2 F g-1 at 1 A g-1 and also exhibits remarkable rate performance. Such remarkable property is attributed to the effective combination of NiCo2S4 plus HPC and their strong chemical bonds, which enable excellent electronic conductivity and abundant exposed electroactive sites. The asymmetric supercapacitor assembled by utilizing NiCo2S4/HPC and active carbon as the positive and negative electrodes, respectively, provide an excellent energy density of 32.05 Wh kg-1 at a power density of 193.9 W kg-1. This work puts forward a practical optimization strategy for metal sulfides used in electrochemical energy storage devices.


Assuntos
Carbono , Lignina , Porosidade , Carvão Vegetal , Sulfetos
2.
Front Pharmacol ; 13: 943111, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935850

RESUMO

Background: Oxidative stress is associated with the pathogenesis of ischemic stroke (±)-5-bromo-2-(5-fluoro-1-hydroxyamyl) benzoate (BFB) is a novel compound modified by dl-3-n-butylphthalide (NBP). Here, we hypothesized that BFB may protect the PC12 cells against H2O2-induced oxidative stress injury through activation of the Nrf2 pathway. Methods: We measured the cell viability and levels of lactate dehydrogenase (LDH), malondialdehyde (MDA), glutathione (GSH), and reactive oxygen species (ROS) to determine the construction of the H2O2-induced models of oxidative stress in PC12 cells. Additionally, apoptotic cell death, mitochondrial membrane potential, and cellular morphology were examined to determine the effect of BFB on oxidative stress injury in H2O2-treated PC12 cells. The expression levels of Nrf2-related and autophagy-related genes and proteins were detected using real time quantative PCR (RT-qPCR), Western Blot, and immunofluorescence analyses. Results: Our study showed that BFB treatment reduced the elevated levels of MDA, LDH, and ROS, and decreased cell viability and GSH in H2O2-treated PC12 cells. We also observed the elevated expression of Nrf2 pathway-related factors and intranuclear transitions and found that Nrf2 inhibitors (ML385) could block the protective effect of BFB. The inhibitory effect of BFB on oxidative stress may be partially regulated by Nrf2 activation, and the initiation and induction of autophagy. Conclusion: BFB inhibited H2O2-induced oxidative stress injury in PC12 cells by activating the Nrf2 pathway, initiating and inducing autophagy, suggesting that BFB may be a promising therapeutic agent in treating neurological disorders like cerebral ischemia.

3.
Int J Biol Macromol ; 190: 11-18, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34478791

RESUMO

The development of advanced energy storage systems, such as rechargeable batteries and supercapacitors (SCs), is one of the great challenges related to energy demand with the rapid development of world economy. Herein, a three-dimensional hierarchical porous lignin-derived carbon/WO3 (HPC/WO3) was prepared by carbonization and solvothermal process. This electrode material for supercapacitor can be operated at a wide voltage window range of -0.4 V to 1.0 V. More importantly, 3HPC/WO3 with ultrahigh mass loading (~3.56 mg cm-2) has excellent specific capacitance of 432 F g-1 at 0.5 A g-1 and cycling stability of 86.6% after 10,000 cycles at 10 A g-1. The as-assembled asymmetrical supercapacitor shows an energy density of 34.2 W h kg-1 at a power density of 237 W kg-1 and energy density of 16 W h kg-1 at a power density is 14,300 W kg-1. A solid-state planar micro-supercapacitor (MSC) was fabricated using HPC/WO3 nanocomposites. Moreover, the calculated specific capacity of MSC was 20 mF cm-2 in polyvinyl alcohol-sulfuric acid gel electrolyte. Overall, through the reasonable design of HPC/WO3 nanocomposite materials and the efficient assembly of MSCs, the performance of the device was greatly improved, thus providing a clear strategy for the development of energy storage devices.


Assuntos
Carbono/química , Capacitância Elétrica , Lignina/química , Óxidos/química , Tungstênio/química , Adsorção , Eletroquímica , Nitrogênio/química , Porosidade , Difração de Raios X
4.
Int J Biol Macromol ; 166: 923-933, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152364

RESUMO

Three-dimensional hierarchical porous carbon is prepared by utilizing enzymatic hydrolysis lignin as a carbon source via hydrothermal carbonization and activation. The complicated operational parameters including temperature, time, concentration and pH in the hydrothermal carbonization are systemically investigated. We employed the hydrochar as electrode for supercapacitors. Accordingly, we not only achieve a high-performance specific capacitance for supercapacitors but also rationalize the effects of hydrothermal conditions on the specific capacitance via various characterizations. The activation process of hydrochar is also studied by comparing various activators and the activator/hydrochar ratios. The obtained materials possess a three-dimensional interconnected hierarchical structure with rational pore size distribution and a specific surface area reach up to 1504 m2 g-1. Then the corresponding supercapacitors achieve a large specific capacitance of 324 F g-1 as the current density is 0.5 A g-1. These supercapacitors acquire an outstanding cycling stability with 99.7% capacitance retention after 5000 cycles. The assembled symmetrical supercapacitors also show a high energy density of 17.9 W h kg-1 and can maintain at 5.6 W h kg-1 even at an ultra-high power density of 50,400 W kg-1.


Assuntos
Carbono/química , Capacitância Elétrica , Lignina/química , Animais , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos/normas , Hidróxidos/química , Compostos de Potássio/química
5.
Zhongguo Zhong Yao Za Zhi ; 40(4): 739-43, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-26137700

RESUMO

To study the pharmacokinetic characteristics and absolute bioavailability of α-asarone through dry powder inhalation in rats, and compare with that through oral administration and intravenous injection. A HPLC method was established for the determination of α-asarone in rat plasma to detect the changes in plasma concentrations of α-asarone through dry powder inhalation (20 mg · kg(-1)), oral administration (80 mg · kg(-1)) and intravenous injection (20 mg · kg(-1)) in rats. DAS 2.0 software was used to calculate the pharmacokinetic parameters. The absolute bioavailability of α-asarone was calculated according to AUC(0-t)) of administration routes and administration doses. According to the results, α-asarone showed good linear relations (r = 0. 999 4) at concentrations between 0.282-14.1 mg · L(-1), with the limit of detection (LOD) at 0.212 mg · L(-1). Through dry powder inhalation, oral administration and intravenous injection of α-asarone, the metabolic processes of α-asarone in rats conformed to one, two and three compartment models respectively, with the elimination half-life of (95.48 ± 48.28), (64.34 ± 27.59), (66.99 ± 29.76) min. According to the bioavailability formula, the absolute bioavailability of α-asarone through dry powder inhalation and oral administration were 78.32% and 33. 60%, respectively. This study showed that significant increase in elimination half-life and absolute bioavailability of α-asarone through dry powder inhalation, which lays a theoretical foundation for preparing α-asarone dry powder inhalers.


Assuntos
Anisóis/farmacocinética , Medicamentos de Ervas Chinesas/farmacocinética , Administração por Inalação , Derivados de Alilbenzenos , Animais , Anisóis/administração & dosagem , Anisóis/sangue , Disponibilidade Biológica , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/análise , Meia-Vida , Masculino , Ratos , Ratos Sprague-Dawley
6.
Yao Xue Xue Bao ; 49(11): 1607-13, 2014 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-25757290

RESUMO

For effective inhalable dry-powder drug delivery, tetrandrine-PLGA (polylactic-co-glycolic acid) nanocomposite particles have been developed to overcome the disadvantages of nanoparticles and microparticles. The primary nanoparticles were prepared by using premix membrane emulsification method. To prepare second particles, they were spray dried. The final particles were characterized by scanning electron microscopy (SEM), dry laser particle size analysis, high performance liquid chromatography (HPLC), X-ray diffraction (XRD), differential scanning calorimetry (DSC), infrared analysis (IR) and confocal laser scanning microscope (CLSM). The average size of the primary particles was (337.5 ± 6.2) nm, while that second particles was (3.675 ± 0.16) µm which can be decomposed into primary nanoparticles in water. And the second particles were solid sphere-like with the drug dispersed as armorphous form in them. It is a reference for components delivery to lung in a new form.


Assuntos
Benzilisoquinolinas/química , Ácido Láctico/química , Nanocompostos/química , Ácido Poliglicólico/química , Administração por Inalação , Varredura Diferencial de Calorimetria , Sistemas de Liberação de Medicamentos , Inaladores de Pó Seco , Microscopia Eletrônica de Varredura , Nanopartículas/química , Tamanho da Partícula , Preparações Farmacêuticas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Difração de Raios X
7.
Zhongguo Zhong Yao Za Zhi ; 39(23): 4583-9, 2014 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-25911806

RESUMO

Relatively uniform-sized nanoparticles made of poly (lactic-co-glycolic acid) (PLGA) were prepared by premix membrane emulsification method. After the drug loading property was completed, the dynamic tissue distribution of nanoparticles was recorded. With the average particle size and span as indexes, membrane pore size, number of passing membrane times, membrane pressure, volume ratio of oil-water phase and the concentration of poly(vinyl alcohol) (PVA) in external water phase were investigated by single factor test, the optimum preparation technology of blank PLGA nanlparticles was as following: pore size of SPG membrane was 1 µm, membrane pressure was 1. 15 MPa, the number of passing membrane time was 3, the mass fraction of PVA of 2%, volume ratio of oil-water phase of 1 : 5. Prepared nanoparticles were round with smooth surface, the mean diameter was 332.6 nm, span was 0.010, the confocal laser scanning microscope (CLSM) concluded that fluorescent substance is uniform composizion in PLGA nanoparticle, and the in vivo imaging technology in mice include that the nanoparticles show good liver and spleen targeting property.


Assuntos
Sistemas de Liberação de Medicamentos/instrumentação , Corantes Fluorescentes/química , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Animais , Portadores de Fármacos/química , Emulsões/química , Camundongos , Camundongos Nus , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
8.
Artigo em Inglês | MEDLINE | ID: mdl-24367386

RESUMO

Huang-Lian-Jie-Du-Tang (HLJDT), a classical Chinese prescription, has been clinically employed to treat cerebral ischemia for thousands of years. Geniposide is the major active ingredient in HLJDT. The aim is to investigate the comparative evaluations on pharmacokinetics of geniposide in MCAO rats in pure geniposide, geniposide : berberine, and geniposide : berberine : baicalin. Obviously, the proportions of geniposide : berberine, geniposide : baicalin, and geniposide : berberine : baicalin were determined according to HLJDT. In our study, the cerebral ischemia model was reproduced by suture method in rats. The MCAO rats were randomly assigned to four therapy groups and orally administered with different prescription proportions of pure geniposide, geniposide : berberine, geniposide : baicalin, and geniposide : berberine : baicalin, respectively. The concentrations of geniposide in rat serum were determined using HPLC, and main pharmacokinetic parameters were investigated. The results indicated that the pharmacokinetics of geniposide in rat serum was nonlinear and there were significant differences between different groups. Berberine might hardly affect the absorption of geniposide, and baicalin could increase the absorption ability of geniposide. Meanwhile, berberine could decrease the absorption increase of baicalin on geniposide.

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