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1.
ACS Nano ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758185

RESUMO

Defect engineering and nitrogen doping being effective strategies for modulating the surface chemical state of the carbon matrix have been widely explored to promote the catalytic activity in the territory of electrochemical energy storage and conversion devices. However, the controllable synthesis of carbon material with high-density specific defects and high nitrogen doping is still full of challenges. Here, we first synthesize one-dimensional necklace-like nitrogen-doped carbon nanochains (N-CNCs) with abundant defects on carbon fiber paper (CFP) by chemical vapor deposition (CVD) method. The resultant nanostructures are a bunch of interconnected carbon spheres with a hollow structure at the internode and present the complete one-dimensional nanochain configuration. Specifically, the N-CNCs with a corrugated surface possesses high content of sp3 defects (31.2%) and nitrogen (23.6 at %). Combining finite element analysis and experimental results, it reveals that the robust shear field generated by etching gas releasing from thermal decomposition of melamine in situ modulates the CVD process via changing the size and force environment of the metal catalyst droplets for formation of N-CNCs. Benefiting from the high ratio of sp3/sp2 and nitrogen doped on the surface, the N-CNCs@CFP displays a superior electrocatalytic performance for CO2RR, delivering CO Faradaic efficiency of 95.9% and a current density of 23.2 mA cm-2 at -0.86 V vs RHE. This work provides promising synthesis strategy and some inspirations for construction of ultradense and specific defects coupling with nitrogen doping sites into carbon materials to achieve high-efficiency electrocatalysis applications.

2.
Small ; 20(11): e2307349, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38105349

RESUMO

Co electroreduction of carbon dioxide and nitrate to synthesize urea provides an alternative strategy to high energy-consumption traditional methods. However, the complexity of the reaction mechanism and the high energy barrier of nitrate reduction result in a diminished production of urea. Herein, a convenient electrodeposition technique to prepare the FeOOH with low spin state iron that increases the yield rate of urea efficiently is employed. According to soft X-ray Absorption Spectroscopy and theoretical calculations, the unique configuration of low spin state iron as electron acceptors can effectively induce electron pair transfer from the occupied σ orbitals of intermediate * NO to empty d orbitals of iron. This σ→d donation mechanism leads to a reduction in the energy barrier associated with the rate-determining step (* NOOH→* NO + * OH), hence augmenting the urea generation. The low spin state iron presents a high urea yield rate of 512 µg h-1  cm-2 , representing approximately two times compared to the medium spin state iron. The key intermediates (* NH2 and * CO) in the formation of C─N bond are detected with in situ Fourier transform infrared spectroscopy. The coupling of * NH2 and * CO contributes to the formation of * CONH2 , which subsequently endures multi-step proton-coupled electron transfer to generate urea.

3.
Chem Commun (Camb) ; 59(22): 3261-3264, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36815681

RESUMO

A quasi-homogenized miniemulsion system enabled by carbon quantum dot solid nanoparticles for biphasic catalysis is proposed, which breaks existing limits for an immiscibly biphasic system and overcomes issues for large-sized solid particle-stabilized emulsion droplets. The presented Pickering miniemulsion features pH-responsive behavior, finally triggering facile product separation and catalyst recycling in one reaction vessel.

4.
Angew Chem Int Ed Engl ; 61(37): e202203836, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35852815

RESUMO

The design of efficient non-noble metal catalysts for CO2 hydrogenation to fuels and chemicals is desired yet remains a challenge. Herein, we report that single Mo atoms with a MoN3 (pyrrolic) moiety enable remarkable CO2 adsorption and hydrogenation to CO, as predicted by density functional theory studies and evidenced by a high and stable conversion of CO2 reaching about 30.4 % with a CO selectivity of almost 100 % at 500 °C and very low H2 partial pressure. Atomically dispersed MoN3 is calculated to facilitate CO2 activation and reduces CO2 to CO* via the direct dissociation path. Furthermore, the highest transition state energy in CO formation is 0.82 eV, which is substantially lower than that of CH4 formation (2.16 eV) and accounts for the dominant yield of CO. The enhanced catalytic performances of Mo/NC originate from facile CO desorption with the help of dispersed Mo on nitrogen-doped carbon (Mo/NC), and in the absence of Mo nanoparticles. The resulting catalyst preserves good stability without degradation of CO2 conversion rate even after 68 hours of continuous reaction. This finding provides a promising route for the construction of highly active, selective, and robust single-atom non-precious metal catalysts for reverse water-gas shift reaction.

5.
J Am Chem Soc ; 144(23): 10193-10200, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35586910

RESUMO

Integrated/cascade plasma-enabled N2 oxidation and electrocatalytic NOx- (where x = 2, 3) reduction reaction (pNOR-eNOx-RR) holds great promise for the renewable synthesis of ammonia (NH3). However, the corresponding activated effects and process of plasma toward N2 and O2 molecules and the mechanism of eNOx-RR to NH3 are unclear and need to be further uncovered, which largely limits the large-scale deployment of this process integration technology. Herein, we systematically investigate the plasma-enabled activation and recombination processes of N2 and O2 molecules, and more meaningfully, the mechanism of eNOx-RR at a microscopic level is also decoupled using copper (Cu) nanoparticles as a representative electrocatalyst. The concentration of produced NOx in the pNOR system is confirmed as a function of the length for spark discharge as well as the volumetric ratio for N2 and O2 feeding gas. The successive protonation process of NOx- and the key N-containing intermediates (e.g., -NH2) of eNOx-RR are detected with in situ infrared spectroscopy. Besides, in situ Raman spectroscopy further reveals the dynamic reconstruction process of Cu nanoparticles during the eNOx-RR process. The Cu nanoparticle-driven pNOR-eNOx-RR system can finally achieve a high NH3 yield rate of ∼40 nmol s-1 cm-2 and Faradaic efficiency of nearly 90%, overperforming the benchmarks reported in the literature. It is anticipated that this work will stimulate the practical development of the pNOR-eNOx-RR system for the green electrosynthesis of NH3 directly from air and water under ambient conditions.


Assuntos
Amônia , Cobre , Amônia/química , Cobre/química , Oxirredução , Espectrofotometria Infravermelho
6.
Chem Soc Rev ; 51(11): 4763-4785, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35584360

RESUMO

The dependence on fossil fuels has caused excessive emissions of greenhouse gases (GHGs), leading to climate changes and global warming. Even though the expansion of electricity generation will enable a wider use of electric vehicles, biotechnology represents an attractive route for producing high-density liquid transportation fuels that can reduce GHG emissions from jets, long-haul trucks and ships. Furthermore, to achieve immediate alleviation of the current environmental situation, besides reducing carbon footprint it is urgent to develop technologies that transform atmospheric CO2 into fossil fuel replacements. The integration of bio-catalysis and electrocatalysis (bio-electrocatalysis) provides such a promising avenue to convert CO2 into fuels and chemicals with high-chain lengths. Following an overview of different mechanisms that can be used for CO2 fixation, we will discuss crucial factors for electrocatalysis with a special highlight on the improvement of electron-transfer kinetics, multi-dimensional electrocatalysts and their hybrids, electrolyser configurations, and the integration of electrocatalysis and bio-catalysis. Finally, we prospect key advantages and challenges of bio-electrocatalysis, and end with a discussion of future research directions.


Assuntos
Dióxido de Carbono , Efeito Estufa , Biotecnologia , Catálise , Combustíveis Fósseis
7.
Expert Opin Drug Deliv ; 19(4): 451-464, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35385376

RESUMO

BACKGROUND: Norcantharidin (NCTD) has a certain degree of hydrophilicity and poor lipophilicity, and has some side-effects, including short t1/2, vascular irritation, cardiotoxicity, and nephrotoxicity, which bring difficulties for formulation research. In this study, we aim to develop a novel nanocarrier to improve encapsulation efficiency, increase sterilization stability, and enhance antitumor activity. METHODS: Phospholipid complexes methods were used for increasing the lipophilicity of norcantharidin (NCTD), then NCTD phospholipid complexes were not only loaded in the oil phase and oil-water interface surface, but also encapsulated in phospholipid bilayers to obtain NCTD liposome-emulsion hybrid (NLEH) delivery system. The in vitro cytotoxicity and apoptosis, in vivo tissue distribution, tumor penetration, heterotopic, and orthotopic antitumor studies were conducted to evaluate therapeutic effect. RESULTS: NLEH exhibited an improved encapsulation efficiency (89.3%) and a better sterilization stability, compared to NCTD liposomes and NCTD emulsions. NLEH can achieve a better antitumor activity by promoting absorption (1.93-fold), prolonging blood circulation (2.08-fold), enhancing tumor-targeting accumulation (1.19 times), improving tumor penetration, and increasing antitumor immunity. CONCLUSIONS: The liposome-emulsion hybrid (LEH) delivery system was potential carrier for NCTD delivery, and LEH could open opportunities for delivery of poorly soluble anticancer drugs, especially drugs that are more hydrophilicity than lipophilicity.


Assuntos
Antineoplásicos , Lipossomos , Antineoplásicos/farmacologia , Apoptose , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Tumoral , Emulsões , Fosfolipídeos
8.
Nano Lett ; 22(7): 3054-3061, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35315677

RESUMO

Novel anode materials for lithium-ion batteries were synthesized by in situ growth of spheres of graphene and carbon nanotubes (CNTs) around silicon particles. These composites possess high electrical conductivity and mechanical resiliency, which can sustain the high-pressure calendering process in industrial electrode fabrication, as well as the stress induced during charging and discharging of the electrodes. The resultant electrodes exhibit outstanding cycling durability (∼90% capacity retention at 2 A g-1 after 700 cycles or a capacity fading rate of 0.014% per cycle), calendering compatibility (sustain pressure over 100 MPa), and adequate volumetric capacity (1006 mAh cm-3), providing a novel design strategy toward better silicon anode materials.

9.
Eur J Med Chem ; 230: 114099, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35007859

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is considered as one of the most dangerous clinical pathogens. Biofilms forming ability of MRSA is also a major cause of drug resistance. Hence, it is in urgent need to develop novel antibacterial/antibiofilm drugs. Fascaplysin with a unique cationic five-ring coplanar backbone is emerging as a potential antibacterial compound. In this study, aiming at developing novel and more effective agents, a series of fascaplysin derivatives and their corresponding ß-carboline precursors have been synthesized. Then their antibacterial/antibiofilm activity and mechanisms against MRSA were investigated for the first time. The results showed that most fascaplysins rather than ß-carboline precursors exhibit superior antimicrobial activity against MRSA ATCC43300, demonstrating the important role of cationic five-ring coplanar backbone playing in antibacterial activity. Among them, 14 and 18 are the most potent compounds with MIC value of 0.098 µg/ml (10-fold lower than vancomycin), and 18 featuring the lowest toxicity. Subsequent mechanisms exploration indicates that 18 has relatively stronger ability to destroy bacterial cell wall and membrane, higher binding affinity to bacterial genomic DNA. Molecular docking study revealed that besides the key role of cationic five-ring coplanar backbone, introduction of N-aryl amide at 9-position of fascaplysin promoted the combination of compound 18 and DNA via additional π-π stacking and hydrogen bonding of the naphthyl group. Moreover, fascaplysins could inhibit MRSA biofilm formation in vitro and bacterial infection in vivo. All these results illustrate that fascaplysin derivative 18 is a strong and safe multi-target antibacterial agent, which makes it an attractive candidate for the treatment of MRSA and its biofilm infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Antibacterianos/farmacologia , Biofilmes , DNA , Indóis , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular
10.
Adv Mater ; 34(7): e2107787, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34800062

RESUMO

Electric vehicles (EVs) are being adopted to replace combustion engine vehicles to reduce greenhouse gas emissions and mitigate climate change; developing batteries with high energy efficiency and long lifespan, in the context of carbon footprint and cost, are essential to ensure the successful transition. Herein, an electrolyte modulator that can effectively mitigate the polarization of lithium-ion batteries, leading to dramatically improved energy efficiency and lifespan, is reported. Under a dynamic stress test that mimics the operations of EVs, commercial pouch cells with a low concentration of electrolyte modulator (0.2 wt% of the electrolyte) exhibit enhanced energy efficiency (87.5% vs 80.4% for the first 500 testing cycles) and prolonged lifespan (fourfold improvement based on 70% energy-output retention). This work provides a simple yet effective strategy toward sustainable electrification of vehicles.

11.
Pharmgenomics Pers Med ; 14: 1315-1329, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34703277

RESUMO

BACKGROUND: Tenofovir alafenamide fumarate (TAF) was approved for HBV treatment in China in 2018. Despite higher antiviral efficacy and less impact on renal function and bone mineral density, the pharmacokinetic profiles of TAF are highly variable. The objectives of this study were to investigate the pharmacokinetics of TAF in the Chinese population and explore the associations between TAF and genetic polymorphisms and non-genetic factors. PATIENTS AND METHODS: A total of 64 healthy Chinese subjects aged 18~65 years old were planned to enroll. According to the dietary intake status, the subjects were divided into two groups (n = 32 per group). The concentrations of TAF and tenofovir were measured by HPLC-MS/MS, and the single-nucleotide polymorphisms were analyzed by MALDI-TOF MS. RESULTS: All the enrolled participants (18-35 years) completed the clinical trial study. Similar to the results reported in other ethnic populations, the pharmacokinetic profiles of TAF and tenofovir were highly variable in the Chinese people, and the HFHC diet can significantly increase the systemic exposure of TAF. We determined both HFHC diet and rs7311358 (SLCO1B3) genotypes were independently associated with TAF AUC 0-t , while HFHC diet, age and rs3740066 (ABCC2) variants were predictive of t1/2 of tenofovir (P < 0.05). The subjects with the AA genotype in rs7311358 had significantly higher TAF AUC0-t values (1.15 times) than those with a G allele, and the t1/2 of tenofovir in the rs3740066 TT genotype group was 1.23 times longer than that of CC genotype group. Furthermore, there was a trend of higher TAF AUC and shorter tenofovir t1/2 for the rs2032582 (ABCB1) T allele and rs3742106 (ABCC4) CC variant, respectively, although not statistically significant in the multiple linear regression analysis. CONCLUSION: This study provided new evidence to suggest a critical link between both genetic and non-genetic factors and TAF pharmacokinetics in the Chinese people.

12.
Int J Pharm ; 602: 120619, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33887396

RESUMO

Combination, synergistic chemotherapy with gemcitabine (GEM) and cisplatin (CDDP) is a common strategy, and has been recommended for tumor treatment due to its promoted therapeutic effect and reduced systemic toxicity. However, this process involves the intravenous infusion of GEM prior to that of CDDP, which is inconvenient for patients and staff. Here, a novel hybrid nano-carrier system comprised of micelles encapsulated within PEGylated liposomes is proposed, in order to combine the unique strengths of each component. CDDP was bonded with PLG-PEG, and then the formed CDDP@PLG-PEG micelles and GEM were co-loaded inside PEGylated liposomes. The hybrid liposomes with the optimized GEM/CDDP ratio (1:0.6) showed a roughly spherical morphology, appropriate drug loading, and sustained release behavior. In vitro, the hybrid liposomes had 1.72-fold increased cellular uptake, and 57.42%-fold decreased IC50 value. In vivo, pharmacokinetic studies showed increased t1/2 values (125.64%- and 128.57%-folds for GEM and CDDP), decreased clearance (41.90%- and 2.37%-folds), and promoted AUC (262.76%- and 4577.24%-folds). Finally, an in vivo antitumor study showed effective activity in regards to lung tumor size and weight, which were 40.48%- and 33.11%-folds that of GEM/CDDP solution. In summary, we demonstrated the development of an effective micelle-containing PEGylated hybrid liposomes for combined GEM/CDDP delivery.


Assuntos
Antineoplásicos , Micelas , Linhagem Celular Tumoral , Cisplatino , Desoxicitidina/análogos & derivados , Humanos , Lipossomos , Polietilenoglicóis , Gencitabina
13.
Int J Nanomedicine ; 16: 2357-2372, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33790554

RESUMO

PURPOSE: Non-small cell lung cancer (NSCLC) is an aggressive tumor with high mortality and poor prognosis. In this study, we designed a liposome encapsulating polymeric micelles (PMs) loaded with vinorelbine (NVB) and cis-diamminedichloroplatinum (II) (cisplatin or CDDP) for the treatment of NSCLC. MATERIALS AND METHODS: Sodium poly(α-l-glutamic acid)-graft-methoxy-polyethylene glycol (PLG-G-PEG5K) was used to prepare NVB-loaded NVB-PMs and CDDP-loaded CDDP-PMs that were co-encapsulated into liposomes by a reverse evaporation method, yielding NVB and CDDP co-delivery liposomes (CoNP-lips) composed of egg phosphatidyl lipid-80/cholesterol/DPPG/DSPE-mPEG2000 at a molar ratio of 52:32:14:2. The CoNP-lips were characterized in terms of particle size, zeta potential, drug content, encapsulation efficiency, and structural properties. Drug release by the CoNP-lips as well as their stability and cytotoxicity was evaluated in vitro, and their antitumor efficacy was assessed in a mouse xenograft model of Lewis lung carcinoma cell-derived tumors. RESULTS: CoNP-lips had a spherical shape with uniform size distribution; the average particle size was 162.97±9.06 nm, and the average zeta potential was -13.02±0.22 mV. In vitro cytotoxicity analysis and the combination index demonstrated that the CoNP-lips achieved a synergistic cytotoxic effect at an NVB:CDDP weight ratio of 2:1 in an NSCLC cell line. There was sustained release of both drugs from CoNP-lips. The pharmacokinetic analysis showed that CoNP-lips had a higher plasma half-life than NP solution, with 6.52- and 8.03-fold larger areas under the receiver operating characteristic curves of NVB and CDDP. CoNP-lips showed antitumor efficacy in tumor-bearing C57BL/6 mice and drug accumulation in tumors via the enhanced permeability and retention effect. CONCLUSION: CoNP-lips are a promising formulation for targeted therapy in NSCLC.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/uso terapêutico , Sistemas de Liberação de Medicamentos , Neoplasias Pulmonares/tratamento farmacológico , Micelas , Polímeros/química , Vinorelbina/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/farmacocinética , Cisplatino/farmacologia , Liberação Controlada de Fármacos , Humanos , Lipossomos , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos C57BL , Nanopartículas/ultraestrutura , Tamanho da Partícula , Polietilenoglicóis/química , Ratos Sprague-Dawley , Distribuição Tecidual , Vinorelbina/farmacocinética , Vinorelbina/farmacologia
14.
Antibiotics (Basel) ; 10(2)2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33672669

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) and its biofilms infection is still a serious threat to global health. It is urgent to develop efficient drugs by repositioning or designing drugs to solve this problem. In this study, the antibacterial/biofilm activity and mechanisms of ivermectin (D) and its 4″-position amino substitution derivative (D4) against MRSA were investigated. The minimum inhibitory concentration (MIC) of D was 20 µg/mL, which is four times higher than D4 (MIC = 5 µg/mL). The mechanism research demonstrated that D4 was more potent than D at destroying bacterial cell wall, permeating cell membrane (6.25-36.0% vs 1.92-6.04%) and binding to MRSA genomic DNA. Moreover, after incubation with 10-40 µg/mL D4 for 24 h, the percentages of biofilm decreased by 21.2-92.9%, which was more effective than D (no significant change at 40 µg/mL). The antibiofilm effect is achieved by regulating the expression of related genes (RSH, relQ, rsbU, sigB, spA, and icaD). Additionally, though the higher hemolysis makes D4 a safety risk for intravenous injection, other administration options could be considered as well. Therefore, all the results have indicated that D4 may be a potential candidate compound for the treatment of MRSA and its biofilm infections.

15.
Nano Lett ; 21(6): 2572-2579, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33650431

RESUMO

Lithium iron phosphate (LiFePO4) is broadly used as a low-cost cathode material for lithium-ion batteries, but its low ionic and electronic conductivity limit the rate performance. We report herein the synthesis of LiFePO4/graphite composites in which LiFePO4 nanoparticles were grown within a graphite matrix. The graphite matrix is porous, highly conductive, and mechanically robust, giving electrodes outstanding cycle performance and high rate capability. High-mass-loading electrodes with high reversible capacity (160 mA h g-1 under 0.2 C), ultrahigh rate capability (107 mA h g-1 under 60 C), and outstanding cycle performance (>95% reversible capacity retention over 2000 cycles) were achieved, providing a new strategy toward low-cost, long-life, and high-power batteries. Adoption of such material leads to electrodes with volumetric energy density as high as 427 W h L-1 under 60 C, which is of great interest for electric vehicles and other applications.

16.
Expert Opin Drug Deliv ; 18(9): 1211-1228, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33719798

RESUMO

INTRODUCTION: Oral absorption of BCS IV drug benefits little from improved dissolution. Therefore, the absorption of BCS IV drug nanocrystals 'as a whole' strategy is preferred, and structural modification of nanocrystals is required. Surface modification helps the nanocrystals maintain particle structure before drug dissolution is needed, thus enhancing the oral absorption of BCS IV drugs and promoting therapeutic effect. Here, the main challenges and solutions of oral BCS IV drug nanocrystals delivery are discussed. Moreover, strategies for nanocrystal surface modification that facilitates oral bioavailability of BCS IV drugs are highlighted, and provide insights for the innovation in oral drug delivery. AREAS COVERED: Promising size, shape, and surface modification of nanocrystals have gained interests for application in oral BCS IV drugs. EXPERT OPINION: Nanocrystal surface modification is a feasible method to maintain the structural integrity of nanocrystals, and the introduced materials can also be modified to integrate additional functions to further facilitate the absorption of nanocrystals. It is expected that the absorption 'as a whole' strategy of nanocrystals will provide different choices for the oral BCS IV drugs.


Assuntos
Nanopartículas , Preparações Farmacêuticas , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos , Solubilidade
17.
J Sci Food Agric ; 101(6): 2371-2379, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33009832

RESUMO

BACKGROUND: Chinese horsebean-chili-paste (CHCP) is a traditional fermented condiment in China, known as 'the soul of Sichuan cuisine'. The horsebean-to-meju phase in its preparation is important for CHCP production and contributes significantly to its taste and odor. In this study, a comprehensive flavor compound profiling analysis of the naturally brewed horsebean meju (NBHM) and the temperature-controlled brewed horsebean meju (TCBHM) was performed with two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOFMS), and the analysis of physicochemical characteristics and free amino acids. Their aroma-active components and characteristic flavor compounds were evaluated. The flavor compounds responsible for differentiating NBHM and TCBHM were also determined based on the Fisher ratio and principal component analysis. RESULTS: The pH and the reducing sugar and amino-acid nitrogen content of NBHM were 5.38, 64.43, and 5.76 g kg-1 , respectively, whereas those of TCBHM were 5.13, 29.20, and 7.43 g kg-1 . A total of 356 volatiles were identified from 2571 compounds, and 257 volatile compounds were identified in NBHM compared to 322 volatiles in TCBHM. These two horsebean mejus (HMs) exhibited a similar proportion profile for 30 aroma-active compounds. Benzoic acid ethyl ester, 4-ethyl-2-methoxy-phenol and argnine were determined to be characteristic flavor components for NBHM, while 1-(2-furanyl)-ethanone, 2,6-dimethyl-pyrazine, threonine, valine and tyrosine were specific to TCBHM. CONCLUSION: Temperature-controlled brewed horsebean meju possessed better physicochemical and flavor characteristics than NBHM. The temperature-controlled brewing technique in CHCP production can be used as a promising alternative to the traditional natural brewing method. © 2020 Society of Chemical Industry.


Assuntos
Manipulação de Alimentos/métodos , Vicia faba/química , China , Condimentos/análise , Fermentação , Alimentos Fermentados/análise , Aromatizantes/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Odorantes/análise , Sementes/química , Paladar , Temperatura
18.
Angew Chem Int Ed Engl ; 60(7): 3587-3595, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33251665

RESUMO

An efficient chemical synthesis route, with an aim of reaching an ultrahigh nitrogen (N)-doping level in carbon materials can provide a platform where the type and amount of N dopant can be tuned over a wide range. We propose a C-S-C linkage-triggered confined-pyrolysis strategy for the high-efficiency in situ N-doping into carbon matrix and an ultrahigh doping level up to 13.5 at %, which is close to the theoretical upper limit (15.2 at %) is realized at a high carbonization temperature of 1000 °C. The pyridinic N is dominant with a maximum percent of 48.7 %. By using I3 - reduction as an example, the resultant NCM-5 exhibits the best activity with a power conversion efficiency of 8.77 %. A pyridinic N site-dependent activity is demonstrated in which the amount of active sites increases with the increase of pyridinic N, and the carbon atom adjacent to electron-withdrawing pyridinic N at the armchair edge acts as the most favorable site for the adsorption of I2 .

19.
Nat Commun ; 11(1): 5215, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060606

RESUMO

The sluggish electrochemical kinetics of sulfur species has impeded the wide adoption of lithium-sulfur battery, which is one of the most promising candidates for next-generation energy storage system. Here, we present the electronic and geometric structures of all possible sulfur species and construct an electronic energy diagram to unveil their reaction pathways in batteries, as well as the molecular origin of their sluggish kinetics. By decoupling the contradictory requirements of accelerating charging and discharging processes, we select two pseudocapacitive oxides as electron-ion source and drain to enable the efficient transport of electron/Li+ to and from sulfur intermediates respectively. After incorporating dual oxides, the electrochemical kinetics of sulfur cathode is significantly accelerated. This strategy, which couples a fast-electrochemical reaction with a spontaneous chemical reaction to bypass a slow-electrochemical reaction pathway, offers a solution to accelerate an electrochemical reaction, providing new perspectives for the development of high-energy battery systems.

20.
AAPS PharmSciTech ; 21(7): 277, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033942

RESUMO

The purpose of this research is to develop a liposomal drug delivery system, which can selectively target hepatocellular carcinoma (HCC) to deliver the antitumor agent N-14NCTDA, a C14 alkyl chain norcantharimide derivative of norcantharidin. N-14NCTDA-loaded liposomes were successfully prepared by lipid membrane hydration and extrusion methods. SP94, a targeting peptide for HCC cells, was attached to the liposomes loaded with N-14NCTDA by the post-insertion method to obtain SP94 modified liposomes (SP94-LPs). SP94-LPs had a significant cytotoxicity against Hep G2 cells with the IC50 of 15.395 ± 0.89 µg/mL, which is lower than that of NCTD-S (IC50 = 20.863 ± 0.56 µg/mL) and GAL-LPs (IC50 = 24.589 ± 1.02 µg/mL). Compared with conventional liposomes (Con-LPs), SP94-LPs showed greater cellular uptake in Hep G2 cells. Likewise, significant tumor suppression was achieved in H22 tumor-bearing mice which were treated with SP94-LPs. The tumor inhibition rate (IRw) of SP94-LPs was 82 ± 0.98%, obviously higher than that of GAL-LPs (69 ± 1.39%), Con-LPs (60 ± 2.78%), and NCTD-S (51 ± 3.67%). SP94-LPs exhibited a significant hepatocellular carcinoma-targeting activity in vitro and in vivo, which will provide a new alternative for hepatocellular carcinoma treatment in future. Graphical Abstract.


Assuntos
Antineoplásicos/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/química , Carcinoma Hepatocelular/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Lipossomos , Neoplasias Hepáticas/tratamento farmacológico , Peptídeos/química , Animais , Antineoplásicos/administração & dosagem , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Cantaridina/análogos & derivados , Células Hep G2 , Humanos , Imidas/química , Camundongos
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