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1.
Polymers (Basel) ; 16(8)2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38675086

RESUMO

Marine anti-fouling coatings represent an efficient approach to prevent and control the marine biofouling. However, a significant amount of antifouling agent is added to improve the static antifouling performance of the coatings, which leads to an issue whereby static antifouling performance conflicts with eco-friendly traits. Herein, this work reports an in situ reduction synthesis of silver nanoparticles (AgNPs) within polymers to produce composite coatings, aiming to solve the aforementioned issue. Firstly, urushiol-based benzoxazine monomers were synthesized by the Mannich reaction, using an eco-friendly natural product urushiol and n-octylamine and paraformaldehyde as the reactants. Additionally, AgNPs were obtained through the employment of free radicals formed by phenolic hydroxyl groups in the urushiol-based benzoxazine monomers, achieved by the in situ reduction of silver nitrate in benzoxazine. Then, the urushiol-based benzoxazine/AgNPs composite coatings were prepared by the thermosetting method. AgNPs exhibit broad-spectrum and highly efficient antimicrobial properties, with a low risk to human health and a minimal environmental impact. The composite coating containing a small amount of AgNPs (≤1 wt%) exhibits effective inhibition against various types of bacteria and marine microalgae in static immersion, thereby displaying outstanding antifouling properties. This organic polymer and inorganic nanoparticle composite marine antifouling coating, with its simple preparation method and eco-friendliness, presents an effective solution to the conflict between static antifouling effectiveness and environmental sustainability in marine antifouling coatings.

2.
Inorg Chem ; 63(12): 5586-5597, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38481363

RESUMO

The development of stable and effective catalysts to convert toxic H2S into high value-added sulfur is essential for production safety and environmental protection. However, the inherent defects of traditional iron- and zirconium-based catalysts, such as poor activity, high oxygen consumption, and low sulfur selectivity, limit their further developments and applications. Herein, the Fe-Zr bimetallic organic framework FeUIO-66(x) with different cubic morphologies was synthesized via a facile solvothermal method. The results indicate that the introduction of Fe not only increases the specific surface area and weak L-sites of the catalyst without changing its crystal structure, which provides enough reaction space and more active sites for the adsorption and activation of H2S, but also reduces the activation energy of the reaction, significantly promoting the selective oxidation of H2S. As a result, the as-obtained FeUIO-66(1) catalyst exhibits the highest desulfurization activity and superior durability and water resistance stability, and its H2S conversion and sulfur selectivity within 50 h are 100 and 88%, respectively. More importantly, the structure of the catalyst after the desulfurization reaction is consistent with that of the fresh counterpart. The study offers new insights into the development of effective and stable bimetallic catalysts to eliminate H2S and recycle sulfur.

3.
Adv Mater ; : e2312934, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349956

RESUMO

Stable Zn anodes with high utilization rate are urgently required to promote the specific and volumetric energy densities of Zn-ion batteries for practical applications. Herein, contrary to the widely utilized surface coating on Zn anodes, this work shows that a zinc foil with a backside coated layer delivers much enhanced cycling stability even under high depth of discharge. The backside coating significantly reduces stress concentration, accelerates heat diffusion, and facilitates electron transfer, thus effectively preventing dendrite growth and structural damage at high Zn utilization. As a result, the developed anode can be stably cycled for 334 h at 85.5% Zn utilization, which outperforms bare Zn and previously reported results on surface-coated Zn foils. An NVO-based full cell also shows stable performance with high Zn utilization rate (69.4%), low negative-positive electrodes ratio (1.44), and high specific/volumetric energy densities (155.8 Wh kg-1/178 Wh L-1), which accelerates the progress toward practical zinc-ion batteries.

4.
Nat Commun ; 15(1): 1263, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341471

RESUMO

Metallic 2M or 1T'-phase transition metal dichalcogenides (TMDs) attract increasing interests owing to their fascinating physicochemical properties, such as superconductivity, optical nonlinearity, and enhanced electrochemical activity. However, these TMDs are metastable and tend to transform to the thermodynamically stable 2H phase. In this study, through systematic investigation and theoretical simulation of phase change of 2M WS2, we demonstrate that ultrathin 2M WS2 has significantly higher intrinsic thermal stabilities than the bulk counterparts. The 2M-to-2H phase transition temperature increases from 120 °C to 210 °C in the air as thickness of WS2 is reduced from bulk to bilayer. Monolayered 1T' WS2 can withstand temperatures up to 350 °C in the air before being oxidized, and up to 450 °C in argon atmosphere before transforming to 1H phase. The higher stability of thinner 2M WS2 is attributed to stiffened intralayer bonds, enhanced thermal conductivity and higher average barrier per layer during the layer(s)-by-layer(s) phase transition process. The observed high intrinsic phase stability can expand the practical applications of ultrathin 2M TMDs.

5.
Angew Chem Int Ed Engl ; 63(9): e202318496, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38180310

RESUMO

High-rate and stable Zn-ion batteries working at low temperatures are highly desirable for practical applications, but are challenged by sluggish kinetics and severe corrosion. Herein, inspired by frost-resistant plants, we report trace hydroxyl-rich electrolyte additives that implement a dual remodeling effect for high-performance low-temperature Zn-ion batteries. The additive with high Zn absorbability not only remodels Zn2+ primary solvent shell by alternating H2 O molecules, but also forms a shielding layer thus remodeling the Zn surface, which effectively enhances fast Zn2+ de-solvation reaction kinetics and prohibits Zn anode corrosion. Taking trace α-D-glucose (αDG) as a demonstration, the electrolyte obtains a low freezing point of -55.3 °C, and the Zn//Zn cell can stably cycle for 2000 h at 5 mA cm-2 under -25 °C, with a high cumulative capacity of 5000 mAh cm-2 . A full battery that stably operates for 10000 cycles at -50 °C is also demonstrated.

6.
Small ; 20(8): e2304734, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37828641

RESUMO

Lithium metal-based rechargeable batteries are attracting increasing attention due to their high theoretical specific capacity and energy density. However, the dendrite growth leads to short circuits or even explosions and rapid depletion of active materials and electrolytes. Here, a functionalized and laminated scaffold (PVDF/TiO@C fiber) based on lithiophilic titanium monoxide is rationally designed to inhibit dendrite growth. Specifically, the bottom TiO@C fiber sublayer provides rich Li nucleation sites and facilitates the formation of stable solid electrolyte interphase. Together with the top lithiophobic PVDF sublayer, the prepared freestanding scaffold can effectively suppress the growth of Li dendrite and ensure stable Li plating/stripping. Based on the dendrite-free deposition, the Li/PVDF/TiO@ C fiber anode enables over 1000 h at a current density of 1 mA cm-2 in a symmetrical cell and delivers superior electrochemical performance in both Li || LFP and Li-S batteries. The functional laminated fiber scaffold design provides essential insights for obtaining high-performance lithium metal anodes.

7.
Molecules ; 28(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38138530

RESUMO

Zwitterionic polymer coatings facilitate the formation of hydration layers via electrostatic interactions on their surfaces and have demonstrated efficacy in preventing biofouling. They have emerged as a promising class of marine antifouling materials. However, designing multifunctional, environmentally friendly, and natural products-derived zwitterionic polymer coatings that simultaneously resist biofouling, inhibit protein adhesion, exhibit strong antibacterial properties, and reduce algal adhesion is a significant challenge. This study employed two diisocyanates as crosslinkers and natural urushiol and ethanolamine as raw materials. The coupling reaction of diisocyanates with hydroxyl groups was employed to synthesize urushiol-based precursors. Subsequently, sulfobetaine moieties were introduced into the urushiol-based precursors, developing two environmentally friendly and high-performance zwitterionic-functionalized polyurushiol antifouling coatings, denoted as HUDM-SB and IPUDM-SB. The sulfobetaine-functionalized polyurushiol coating exhibited significantly enhanced hydrophilicity, with the static water contact angle reduced to less than 60°, and demonstrated excellent resistance to protein adhesion. IPUDM-SB exhibited antibacterial efficacy up to 99.9% against common Gram-negative bacteria (E. coli and V. alginolyticus) and Gram-positive bacteria (S. aureus and Bacillus. sp.). HUDM-SB achieved antibacterial efficacy exceeding 95.0% against four bacterial species. Furthermore, the sulfobetaine moieties on the surfaces of the IPUDM-SB and HUDM-SB coatings effectively inhibited the growth and reproduction of algal cells by preventing microalgae adhesion. This zwitterionic-functionalized polyurushiol coating does not contain antifouling agents, making it a green, environmentally friendly, and high-performance biomaterial-based solution for marine antifouling.


Assuntos
Incrustação Biológica , Incrustação Biológica/prevenção & controle , Escherichia coli , Staphylococcus aureus , Polímeros/farmacologia , Antibacterianos/farmacologia
8.
Polymers (Basel) ; 15(20)2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37896337

RESUMO

Nanocellulose hydrogels are a crucial category of soft biomaterials with versatile applications in tissue engineering, artificial extracellular matrices, and drug-delivery systems. In the present work, a simple and novel method, involving the self-assembly of cellulose nanocrystals (CNCs) induced by tannic acid (TA), was developed to construct a stable hydrogel (SH-CNC/TA) with oriented porous network structures. The gelation process is driven by the H-bonding interaction between the hydroxyl groups of CNCs and the catechol groups of TA, as substantiated by the atoms in molecules topology analysis and FTIR spectra. Interestingly, the assembled hydrogels exhibited a tunable hierarchical porous structure and mechanical moduli by varying the mass ratio of CNCs to TA. Furthermore, these hydrogels also demonstrate rapid self-healing ability due to the dynamic nature of the H-bond. Additionally, the structural stability of the SH-CNC/TA hydrogel could be further enhanced and adjusted by introducing coordination bonding between metal cations and TA. This H-bonding driven self-assembly method may promote the development of smart cellulose hydrogels with unique microstructures and properties for biomedical and other applications.

9.
Polymers (Basel) ; 15(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37571113

RESUMO

Ionic conductive hydrogels have attracted increasing research interest in flexible electronics. However, the limited resilience and poor fatigue resistance of current ionic hydrogels significantly restrict their practical application. Herein, an urushiol-based ionic conductive double network hydrogel (PU/PVA-Li) was developed by one-pot thermal initiation polymerization assisted with freeze-thaw cycling and subsequent LiCl soaking. Such a PU/PVA-Li hydrogel comprises a primary network of covalently crosslinked polyurushiol (PU) and a secondary network formed by physically crosslinked poly(vinyl alcohol) (PVA) through crystalline regions. The obtained PU/PVA-Li hydrogel demonstrates exceptional mechanical properties, including ultrahigh strength (up to 3.4 MPa), remarkable toughness (up to 1868.6 kJ/m3), and outstanding fatigue resistance, which can be attributed to the synergistic effect of the interpenetrating network structure and dynamic physical interactions between PU and PVA chains. Moreover, the incorporation of LiCl into the hydrogels induces polymer chain contraction via ionic coordination, further enhancing their mechanical strength and resilience, which also impart exceptional ionic conductivity (2.62 mS/m) to the hydrogels. Based on these excellent characteristics of PU/PVA-Li hydrogel, a high-performance flexible strain sensor is developed, which exhibits high sensitivity, excellent stability, and reliability. This PU/PVA-Li hydrogel sensor can be effectively utilized as a wearable electronic device for monitoring various human joint movements. This PU/PVA-Li hydrogel sensor could also demonstrate its great potential in information encryption and decryption through Morse code. This work provides a facile strategy for designing versatile, ultrastrong, and tough ionic conductive hydrogels using sustainable natural extracts and biocompatible polymers. The developed hydrogels hold great potential as promising candidate materials for future flexible intelligent electronics.

10.
Polymers (Basel) ; 15(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37242960

RESUMO

Benzoxazine resins are new thermosetting resins with excellent thermal stability, mechanical properties, and a flexible molecular design, demonstrating promise for applications in marine antifouling coatings. However, designing a multifunctional green benzoxazine resin-derived antifouling coating that combines resistance to biological protein adhesion, a high antibacterial rate, and low algal adhesion is still challenging. In this study, a high-performance coating with a low environmental impact was synthesized using urushiol-based benzoxazine containing tertiary amines as the precursor, and a sulfobetaine moiety into the benzoxazine group was introduced. This sulfobetaine-functionalized urushiol-based polybenzoxazine coating (poly(U-ea/sb)) was capable of clearly killing marine biofouling bacteria adhered to the coating surface and significantly resisting protein attachment. poly(U-ea/sb) exhibited an antibacterial rate of 99.99% against common Gram negative bacteria (e.g., Escherichia coli and Vibrio alginolyticus) and Gram positive bacteria (e.g., Staphylococcus aureus and Bacillus sp.), with >99% its algal inhibition activity, and it effectively prevented microbial adherence. Here, a dual-function crosslinkable zwitterionic polymer, which used an "offensive-defensive" tactic to improve the antifouling characteristics of the coating was presented. This simple, economic, and feasible strategy provides new ideas for the development of green marine antifouling coating materials with excellent performance.

11.
Nat Commun ; 14(1): 641, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36746943

RESUMO

Achieving long-term stable zinc anodes at high currents/capacities remains a great challenge for practical rechargeable zinc-ion batteries. Herein, we report an imprinted gradient zinc electrode that integrates gradient conductivity and hydrophilicity for long-term dendrite-free zinc-ion batteries. The gradient design not only effectively prohibits side reactions between the electrolyte and the zinc anode, but also synergistically optimizes electric field distribution, zinc ion flux and local current density, which induces preferentially deposited zinc in the bottom of the microchannels and suppresses dendrite growth even under high current densities/capacities. As a result, the imprinted gradient zinc anode can be stably cycled for 200 h at a high current density/capacity of 10 mA cm-2/10 mAh cm-2, with a high cumulative capacity of 1000 mAh cm-2, which outperforms the none-gradient counterparts and bare zinc. The imprinted gradient design can be easily scaled up, and a high-performance large-area pouch cell (4*5 cm2) is also demonstrated.

12.
Adv Mater ; 35(6): e2207573, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36404070

RESUMO

Aqueous zinc-ion batteries are highly desirable for sustainable energy storage, but the undesired Zn dendrites growth severely shortens the cycle life. Herein, a triple-gradient electrode that simultaneously integrates gradient conductivity, zincophilicity, and porosity is facilely constructed for a dendrite-free Zn anode. The simple mechanical rolling-induced triple-gradient design effectively optimizes the electric field distribution, Zn2+ ion flux, and Zn deposition paths in the Zn anode, thus synergistically achieving a bottom-up deposition behavior for Zn metals and preventing the short circuit from top dendrite growth. As a result, the electrode with triple gradients delivers a low overpotential of 35 mV and operates steadily over 400 h at 5 mA cm-2 /2.5 mAh cm-2 and 250 h at 10 mA cm-2 /1 mAh cm-2 , far surpassing the non-gradient, single-gradient and dual-gradient counterparts. The well-tunable materials and structures with the facile fabrication method of the triple-gradient strategy will bring inspiration for high-performance energy storage devices.

13.
Front Chem ; 10: 879605, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572108

RESUMO

In this work, urushiol-based polybenzoxazine is cured by the Lewis acid (FeCl3, AlCl3, and CuCl2) at low temperature instead of high thermal curing temperature. The effect of the Lewis acid on structures and properties of the polymers is revealed. The relating urushiol-based benzoxazine monomer (BZ) was synthesized by natural urushiol, formaldehyde, and n-octylamine. The monomer was reacted with the Lewis acid with a molar ratio of 6:1 (Nmonomer: NMetal) at 80°C to obtain films that can be cured at room temperature. The chemical structures of benzoxazine monomers were identified by Fourier-transform infrared spectroscopy (FTIR) and 1H nuclear magnetic resonance spectroscopy (1H-NMR). The interaction between the metal ion and the polymers is revealed by X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance-FTIR (ATR-FTIR). The effect of the Lewis acid on the mechanical properties, wettability, and thermal stability was investigated. The results show that the benzoxazine cured by Cu2+ has a better performance than that cured by Al3+ and Fe3+.

14.
RSC Adv ; 12(17): 10766-10777, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35425021

RESUMO

The economic loss and environmental damage caused by metal corrosion is irreversible. Thus, effective methods, such as coating technologies are used to protect metal surfaces from corrosion. In this work, cardanol-based benzoxazine (CB) was synthesized by a solvent-free method using cardanol, paraformaldehyde and n-octylamine. A cardanol-based benzoxazine copper polymer (CBCP) with good mechanical properties was then prepared by CuCl2 catalysis and can be cured at room temperature. Subsequently, polyimide corrosion inhibitors with a two-dimensional sheet structure (pyromellitic dianhydride polyimide (PDPI) and 1,4,5,8-naphthalene tetracarboxylic dianhydride polyimide (NDPI)) were designed and prepared. Lastly, PDPI or NDPI was mixed with CBCP to obtain two-dimensional lamellar polyimide/cardanol-based benzoxazine copper polymer composite coatings. The Tafel curves and electrochemical impedance spectroscopy (EIS) measurements showed composite coatings with good corrosion resistance in different corrosive media. Compared to CBCP coating, the anticorrosion performance of the composite coatings improved obviously, especially the coating obtained with 0.5 wt% PDPI. It exhibits a high polarization resistance (3.874 × 109 Ω), a high protection efficiency (99.99% and 97.98%) and low corrosion rate (3.376 × 10-6 mm year-1). This work suggested a facile and eco-friendly strategy for preparing bio-based anticorrosive composite coatings from low cost and abundant cardanol and polyimide corrosion inhibitors, which will significantly promote their application in metal anticorrosion.

15.
Plant Dis ; 106(8): 2031-2038, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35124993

RESUMO

Aconitum kusnezoffii is a perennial medicinal plant that belongs to the Ranunculaceae family and is distributed mainly in Northeast and North China. In July 2018, a typical southern blight disease of A. kusnezoffii was observed in commercial fields of Qingyuan County, Fushun City, Liaoning Province, China. The fungus mainly infected stem base and tuberous roots of the plant by wrapping the hyphae and absorbing nutrition, resulting in tuberous root wilted or whole plant death. Morphological characteristics of colony and sclerotia of three representative strains isolated from the diseased plants differed from those of Sclerotium rolfsii isolated from A. carmichaelii. Sclerotia were large (0.8 to 5.1 mm), reddish-brown, and irregular and had pitted surfaces, and the hyphae were white, compact, or fluffy, with a growth rate ranging from 8.0 to 10.1 mm/day. Phylogenetic analysis of the internal transcribed spacer and the large subunit sequences of Akln6, Akln9, and Akln15 showed that three strains isolated from A. kusnezoffii formed a unique and well-supported clade that groups with the reference isolates of S. delphinii. Based on phylogenetic analysis and cultural and morphological characteristics, the three isolates of A. kusnezoffii were identified as S. delphinii. The optimum temperature for mycelial growth of the three tested isolates was 30°C, and sclerotia formed and matured more easily at 20°C. Light promoted the growth of mycelial, whereas dark was beneficial to the formation and maturation of sclerotia. The pathogenicity of S. delphinii showed stronger than S. rolfsii at low temperature (20°C). This is the first report of S. delphinii causing southern blight on A. kusnezoffii in China, and this finding provides a basis for disease-accurate diagnosis and the development of effective management strategies.


Assuntos
Aconitum , Aconitum/microbiologia , Basidiomycota , Fungos , Filogenia , Doenças das Plantas/microbiologia
16.
J Exp Bot ; 72(4): 1449-1459, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33165537

RESUMO

Bicarbonate (NaHCO3) present in soils is usually considered to be a mixed stress for plants, with salts and high pH. NaHCO3-specific signaling in plants has rarely been reported. In this study, transcriptome analyses were conducted in order to identify NaHCO3-specific signaling in Arabidopsis. Weighted correlation network analysis was performed to isolate NaHCO3-specific modules in comparison with acetate treatment. The genes in the NaHCO3-root-specific module, which exhibited opposite expression to that in sodium acetate treatments, were further examined with their corresponding knock-out mutants. The gene Exclusively Bicarbonate Sensitive 1 (EBS1) encoding an S-ribonuclease binding protein, was identified to be specifically involved in plant tolerance to NaHCO3, but not to the other two alkaline salts, acetate and phosphate. We also identified the genes that are commonly regulated by bicarbonate, acetate and phosphate. Multiple brassinosteroid-associated gene ontology terms were enriched in these genes. Genetic assays showed that brassinosteroid signaling positively regulated plant tolerance to NaHCO3 stress, but negatively regulated tolerance to acetate and phosphate. Overall, our data identified bicarbonate-specific genes, and confirmed that alkaline stress is mainly dependent on the specificities of the weak acid ions, rather than high pH.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis , Bicarbonatos/farmacologia , Brassinosteroides/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Transporte , Regulação da Expressão Gênica de Plantas , Ribonucleases , Bicarbonato de Sódio/farmacologia , Esteroides Heterocíclicos , Estresse Fisiológico
17.
Planta ; 253(1): 2, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33247370

RESUMO

MAIN CONCLUSION: Methyl jasmonate promotes the synthesis of rosmarinic acid in Salvia miltiorrhiza Bunge and Salvia castanea f. tomentosa Stib, and it promotes the latter more strongly. Salvia miltiorrhiza Bunge (SMB) is a traditional Chinese medicinal material, its water-soluble phenolic acid component rosmarinic acid has very important medicinal value. Salvia castanea f. tomentosa Stib (SCT) mainly distributed in Nyingchi, Tibet. Its pharmacological effects are similar to SMB, but its rosmarinic acid is significantly higher than the former. Methyl jasmonate (MJ) as an inducer can induce the synthesis of phenolic acids in SMB and SCT. However, the role of MJ on rosmarinic acid in SMB is controversial. Therefore, this study used SMB and SCT hair root as an experimental material and MJ as a variable. On one hand, exploring the controversial reports in SMB; on the other hand, comparing the differences in the mechanism of action of MJ on the phenolic acids in SMB and SCT. The content of related metabolites and the expression of key genes in the synthesis pathway of rosmarinic acid was analyzed by 1H-NMR combined with qRT-PCR technology. Our research has reached the following conclusions: first of all, MJ promotes the accumulation of rosmarinic acid and related phenolic acids in the metabolic pathways of SMB and SCT. After MJ treatment, the content of related components and gene expression are increased. Second, compared to SMB, SCT has a stronger response to MJ. It is speculated that the different responses of secondary metabolism-related genes to MJ may lead to different metabolic responses of salvianolic acid between the two.


Assuntos
Cinamatos , Depsídeos , Raízes de Plantas , Salvia miltiorrhiza , Salvia , Acetatos/farmacologia , Cinamatos/metabolismo , Ciclopentanos/farmacologia , Depsídeos/metabolismo , Oxilipinas/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Salvia/efeitos dos fármacos , Salvia/metabolismo , Salvia miltiorrhiza/efeitos dos fármacos , Salvia miltiorrhiza/metabolismo , Tibet , Ácido Rosmarínico
18.
Molecules ; 25(9)2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32353926

RESUMO

Salvia mltiorrhiza Bunge (SMB) is native to China, whose dried root has been used as medicine. A few chromatographic- or spectrometric-based methods have already been used to analyze the lipid-soluble components in SMB. However, the methodology of qNMR on the extracts of fresh SMB root has not been verified so far. The purpose of this study was to establish a fast and simple method to quantify the tanshinone I, tanshinone IIA, dihydrotanshinone, and cryptotanshinone in fresh Salvia Miltiorrhiza Bunge root without any pre-purification steps using 1H-NMR spectroscopy. The process is as follows: first, 70% methanol aqueous extracts of fresh Salvia Miltiorrhiza Bunge roots were quantitatively analyzed for tanshinone I, tanshinone IIA, dihydrotanshinone, and cryptotanshinone using 1H-NMR spectroscopy. Different internal standards were tested and the validated method was compared with HPLC. 3,4,5-trichloropyridine was chosen as the internal standard. Twelve samples of Salvia Miltiorrhiza Bunge were quantitatively analyzed by qNMR and HPLC respectively. Then, the results were analyzed by chemometric approaches. This NMR method offers a fast, stable, and accurate analysis of four ketones: tanshinone I, tanshinone IIA, dihydrotanshinone, and cryptotanshinone in fresh roots of Salvia Miltiorrhiza Bunge.


Assuntos
Cetonas/análise , Extratos Vegetais/análise , Salvia miltiorrhiza/química , Abietanos/análise , China , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Furanos/análise , Limite de Detecção , Espectroscopia de Ressonância Magnética , Medicina Tradicional Chinesa , Fenantrenos/análise , Raízes de Plantas , Prótons , Piridinas/análise , Quinonas , Reprodutibilidade dos Testes
19.
RSC Adv ; 10(24): 13936-13943, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35498472

RESUMO

Silver nanoparticle-based coatings have been regarded as promising candidates for marine antifouling. However, current toxic fabrication methods also lead to environment risks. Nanoparticle agglomeration, poor compatibility with polymer, and rapid release of Ag+ result in short-term efficacy. In this study, a facile one-pot synthesis method of silver nanoparticles (AgNPs) encapsulated in polymeric urushiol (PUL) was developed. AgNPs were synthesized in situ by natural urushiol, serving as a reductant, dispersant and surfactant. Simultaneously, silver nitrate catalyzed the polymerization of urushiol into PUL. This in situ reduction method made AgNPs uniformly distributed in the polymer matrix. The binding between the AgNPs and the PUL resulted in the stable release of Ag+. Results showed the antibacterial rate of a 0.1% AgNPs coating is 100% in laboratory experiments. This environment-friendly coating showed good microbial inhibition performance with long-term (120 days) marine antifouling efficacy. This study shows the potential of preparing an eco-friendly coating with long-term marine antifouling ability.

20.
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