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1.
J Am Chem Soc ; 146(14): 9819-9827, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38546207

RESUMO

Iron-based phosphate cathode of Na4Fe3(PO4)2(P2O7) has been regarded as a low-cost and structurally stable cathode material for Na-ion batteries (NIBs). However, their practical application is greatly hindered by the insufficient electrochemical performance and limited energy density. Here, we report a new iron-based phosphate cathode of Na4.5Fe3.5(PO4)2.5(P2O7) with the intergrown heterostructure of the maricite-type NaFePO4 and orthorhombic Na4Fe3(PO4)2(P2O7) phases at a mole ratio of 0.5:1. Benefited from the increased composition ratio and the spontaneous activation of the maricite-type NaFePO4 phase, the as-prepared Na4.5Fe3.5(PO4)2.5(P2O7) composites deliver a reversible capacity over 130 mA h g-1 and energy density close to 400 W h kg-1, which is far beyond that of the single-phase Na4Fe3(PO4)2(P2O7) cathode (∼120 mA h g-1 and ∼350 W h kg-1). Moreover, the kg-level products from the scale-up synthesis demonstrate a stable cycling performance over 2000 times at 3 C in pouch cells. We believe that our findings could show the way forward the practical application of the iron-based phosphate cathodes for NIBs.

2.
J Environ Manage ; 366: 121532, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38986382

RESUMO

Injection of an alkaline absorbent into the flue gas can significantly reduce SO2 and SO3 emissions. The article presents alkaline absorbents employed in industrial processes to remove SO2 and SO3 from flue gases, detailing their characteristics and applications across various process conditions. It summarizes the mechanisms and influencing factors behind SO2 and SO3 removal, outlines the impact of multi-component gases, particularly SO2, on SO3 removal in actual flue gases, and elucidates this competitive phenomenon from a theoretical standpoint. The article compares the application scenarios and efficiencies of alkaline absorbents across different processes, identifies the optimal combinations of various absorbents and processes, and proposes a synergistic approach for the removal of SO2 and SO3. The findings demonstrate that by injecting calcium- or sodium-based absorbents into dry processes, SO2 and SO3 can be removed efficiently and cost-effectively, with process optimization and absorbent modifications further enhancing the SOx removal efficiency. In the future, by blending two or more absorbents and applying them to dry processes, a synergistic removal of SO2 and SO3 can be achieved.

3.
Mikrochim Acta ; 190(2): 49, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36630016

RESUMO

A "turn-on" inverse opal photonic crystal fluorescent sensing film infiltrated with a coumarin derivative is reported for the reliable and accurate detection of cysteine in human serum and fluorescence imaging of living cells. The coumarin derivative containing allyl ester specifically reacts with cysteine by ammonolysis to generate a fluorescent product whose emission wavelength is at ~ 535 nm, providing a selective fluorescence detection for cysteine. The emitted fluorescence is significantly enhanced due to the slow photon effect derived from the photonic crystal film. This is because the emission wavelength is overlapped with the blue-band edge of the photonic stopband of the selected inverse opal film. The fluorescence enhancement effect endows the prepared inverse opal film with highly sensitive detection with a limit of detection of 3.23 × 10-9 mol/L and a wide linear detection range of 1 × 10-7 - 1 × 10-3 mol/L. A fast response within 30 s toward cysteine is also achieved due to the three-dimensional interconnected macroporous structure with a high-specific surface area of the inverse opal film. The prepared inverse opal fluorescent sensing film has been successfully applied to the detection of cysteine in human serum and bioimaging of living cells. In the diluted human serum, the recoveries for the detection of cysteine were 97.92 - 107.20%, and the relative standard deviations were 2.61-9.04%, demonstrating the potential applicability of the inverse opal fluorescent sensing film to real sample analysis. The method may provide a universal strategy for constructing various photonic crystal fluorescent sensing films by using different fluorescent probes.


Assuntos
Cisteína , Corantes Fluorescentes , Humanos , Corantes Fluorescentes/toxicidade , Corantes Fluorescentes/química , Fótons , Óptica e Fotônica
4.
Chemistry ; 28(66): e202202105, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-35998025

RESUMO

Herein, the synthesis of a new type of catalyst, SBA-M (Schiff complex of different metal types grafted on SBA-15) based on a quaternization reaction, is described. Various amounts of ionic liquid were grafted into the pore channels of SBA-15 using the post-grafting method, which allowed the ionic liquid to be grafted into the pore channels restrictively. Notably, over six cycles, SBA-Mn (0.2) has been shown to maintain its catalytic activity and stability. In addition, a reaction mechanism for the cycloaddition of CO2 with epoxides based on density-functional theory is proposed. The cycloaddition reaction of CO2 and epoxides is an efficient way of carbon fixation. It is demonstrated that the metal coordinated with the oxygen atom of the epoxides and that a halogen attacked the carbon of epoxides. Moreover, theoretical calculations and synthesis strategy provide a new approach for CO2 conversion.

5.
Analyst ; 147(3): 436-442, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35048914

RESUMO

Tartrazine, as a synthetic food colorant, is harmful to health upon excessive intake. In this study, we developed a simple, sensitive and ultrafast method to detect tartrazine effectively. Specifically, we successfully used ascorbic acid-functionalized anti-aggregated Au nanoparticles (AuNPs) as enhanced substrates to detect tartrazine in drinks using metal enhanced fluorescence (MEF) and surface-enhanced Raman scattering (SERS) piecewise linearly. The fluorescence intensity and Raman signals of the tartrazine solution enhanced after the addition of AuNPs. There was a good linear correlation between the fluorescence intensity and the concentration of tartrazine from 2.0 µM to 40.0 µM, and the limit of detection (LoD) was 15.4 nM. In addition, the Raman intensity also increased linearly with an increase in the concentration of tartrazine in a wide range (1.0 × 10-5 µM to 1.0 × 10-1 µM) and a lower LoD (0.8 pM) was achieved compared with the results from the fluorescence technique. Both fluorescence and SERS can immediately detect tartrazine in drinks after the substrate was mixed with analytes. Hence, the as-prepared anti-aggregated AuNPs as substrate material achieved a highly sensitive, selective and ultrafast detection of tartrazine via fluorescence and Raman techniques in a wide detection range, providing a novel strategy for the detection of food additives.


Assuntos
Nanopartículas Metálicas , Tartrazina , Ácido Ascórbico , Ouro , Limite de Detecção , Análise Espectral Raman
6.
Chemistry ; 27(60): 14947-14963, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34546603

RESUMO

A series of MOFs with a 6-connected spn topology were synthesized (MOF-808-(Zr, Hf), PCN-777-(Zr, Hf), MOF-818-(Zr, Hf)). Through the in situ DRIFTS of NH3 adsorption-desorption, we found that the activated catalyst mainly contains Lewis acid sites. The effects of different organic ligands on the Lewis acid of the Zr6 cluster were analyzed by XPS and NH3 -TPD, and the relative Lewis acidity of the same metal was obtained: PCN-777>MOF-808>MOF-818. In the Py-FTIR results, we confirmed that MOF-818 has a higher acid site density. In the activity test, MOFs with mesoporous structure showed better catalytic activity under normal temperature and pressure. Among them, MOF-818 can still maintain a high degree of crystallinity after catalysis. Finally, we use density functional theory to propose the mechanism of the cycloaddition reaction of carbon dioxide and styrene oxide. The results show that the metal is coordinated with styrene oxide and halogens attack the ß carbon of the epoxide.

7.
J Am Chem Soc ; 141(15): 6362-6374, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30882218

RESUMO

A number of recent studies have shown that the nonradiative voltage losses in organic solar cells can be suppressed in systems with low energetic offsets between donor and acceptor molecular states, but the physical reasons underpinning this remain unclear. Here, we present a systematic study of 18 different donor/acceptor blends to determine the effect that energetic offset has on both radiative and nonradiative recombination of the charge-transfer (CT) state. We find that, for certain blends, low offsets result in hybridization between charge-transfer and lowest donor or acceptor exciton states, which leads to a strong suppression in the nonradiative voltage loss to values as low as 0.23 V associated with an increase in the luminescence of the CT state. Further, we extend a two-state CT-state recombination model to include the interaction between CT and first excited states, which allows us to explain the low nonradiative voltage losses as an increase in the effective CT to ground state oscillator strength due to the intensity borrowing mechanism. We show that low nonradiative voltage losses can be achieved in material combinations with a strong electronic coupling between CT and first excited states and where the lower band gap material has a high oscillator strength for transitions from the excited state to the ground state. Finally, from our model we propose that achieving very low nonradiative voltage losses may come at a cost of higher overall recombination rates, which may help to explain the generally lower FF and EQE of highly hybridized systems.

8.
Chemphyschem ; 20(7): 946-952, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30803116

RESUMO

Anisotropic slippery surfaces are widely used in anti-fouling, smart control of liquid movement and directional liquid transportation. However, anisotropic slippery liquid-infused porous surfaces (SLIPS) cannot meet the need of practical applications owing to loss and contamination of liquid lubricants. Inspired by solid epicuticular wax on the surface of land plant leaves, we herein report a type of biomimetic anisotropic solid slippery surface (ASSS) based on paraffin wax-incorporated paper with directional micro-grooves. This ASSS material shows anisotropic sliding behavior for liquid droplets with different surface tensions. It is demonstrated to be of excellent stability compared with SLIPS as the solid lubricant cannot be lost and stain the contacting surfaces. It also exhibits outstanding acid and alkali corrosion resistance and restoration capability upon physical damage. Both hydrophilic and hydrophobic contaminants on our ASSS can be self-cleaned by using only water droplets. Our ASSS extends the fabrication of new slippery materials and overcomes some drawbacks of SLIPS.

9.
Bioorg Med Chem Lett ; 27(17): 4150-4155, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28754362

RESUMO

The crystal structure of viral infectivity factor (Vif) was reported recently, which makes it possible to design new inhibitors against Vif by structure-based drug design. Through analysis of the protein surface of Vif, the C2 pocket located in the N-terminal was found, which is suit for developing small molecular inhibitors. Then, in our article, fragment-based virtual screening (FBVS) was conducted and a series of fragments was obtained, among which, Zif-1 bearing indole scaffold and pyridine ring can form H-bonds with Tyr148 and Ile155. Subsequently, 19 derivatives of Zif-1 were synthesized. Through the immune-fluorescence staining and Western blot assays, Zif-15 shows potent activity in inhibiting Vif-mediated A3G degradation. Further docking experiment shows that Zif-15 form H-bond interactions with residues His139, Tyr148 and Ile155. Therefore, Zif-15 is a promising lead compound against Vif that can be used to treat AIDS.


Assuntos
Fármacos Anti-HIV/farmacologia , Desenho de Fármacos , HIV-1/efeitos dos fármacos , Indóis/farmacologia , Produtos do Gene vif do Vírus da Imunodeficiência Humana/antagonistas & inibidores , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Relação Dose-Resposta a Droga , Indóis/síntese química , Indóis/química , Estrutura Molecular , Relação Estrutura-Atividade
10.
Bioorg Med Chem Lett ; 24(3): 799-807, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24418772

RESUMO

In this research, a series of 4-(1,2,3-triazol-1-yl)coumarin conjugates were synthesized and their anticancer activities were evaluated in vitro against three human cancer cell lines, including human breast carcinoma MCF-7 cell, colon carcinoma SW480 cell and lung carcinoma A549 cell. To increase the biological potency, structural optimization campaign was conducted focusing on the C-4 position of 1,2,3-triazole and the C-6, C-7 positions of coumarin. In addition, to further evaluate the role of 1,2,3-triazole and coumarin for antiproliferative activity, 9 compounds possessing 4-(piperazin-1-yl)coumarin framework and 3 derivatives baring quinoline core were also synthesized. By MTT assay in vitro, most of the compounds display attractive antitumor activities, especially 23. Further flow cytometry assays demonstrate that compound 23 exerts the antiproliferative role through arresting G2/M cell-cycle and inducing apoptosis.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cumarínicos/síntese química , Cumarínicos/farmacologia , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cumarínicos/química , Citometria de Fluxo , Humanos , Concentração Inibidora 50 , Células MCF-7 , Triazóis/síntese química , Triazóis/química , Triazóis/farmacologia
11.
J Phys Chem B ; 128(7): 1737-1747, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38326970

RESUMO

In order to overcome the drawbacks of conventional absorbents, which exhibit slow absorption rates and low absorption loads, this study suggests enhancing the absorbent system for CO2 absorption by incorporating a nonaqueous solvent into 1,3-propanediamine (DAP) and tetramethylethylenediamine (TMEDA), resulting in a two-phase system. The mechanism of solvent absorption of CO2 was investigated using nuclear magnetic resonance (NMR) carbon spectroscopy. By comparing the absorption load, fraction ratio, and viscosity of different absorbents after absorbing carbon dioxide, the two-phase absorbents with good performance were selected. The poor water absorbent consisting of the DAP/TMEDA system exhibited an absorption load of 3.8 mol/kg, surpassing that of the conventional 30% ethanolamine solution. A nonaqueous solvent is added to the system to replace some of the water to reduce the fraction. After adding different nonaqueous solvents, the phase separation system was screened after 2 h of CO2 absorption. The system with good performance was tested for the absorption of the solution under different amine concentration and water concentration tests. It is found that the absorption load of the DAP/TMEDA/diglyme system is 3.2 mol/kg, but the fraction can be reduced to 38%. The significant reduction in rich phase volume is beneficial for reducing the size and cost of regeneration tower. According to NMR detection and quantum chemical calculations, it was found that DAP/TMEDA absorbs carbon dioxide to form carbamate. DAP acts as the main absorbent, while TMEDA and nonaqueous solvents do not participate in the absorption reaction. Nonaqueous solvents were found to accelerate the solution phase separation due to the salt precipitation reaction.

12.
Abdom Radiol (NY) ; 49(6): 1805-1815, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38462557

RESUMO

OBJECTIVE: We aim to construct a magnetic resonance imaging (MRI)-based multi-sequence multi-regional radiomics model that will improve the preoperative prediction ability of lymph node metastasis (LNM) in T3 rectal cancer. METHODS: Multi-sequence MRI data from 190 patients with T3 rectal cancer were retrospectively analyzed, with 94 patients in the LNM group and 96 patients in the non-LNM group. The clinical factors, subjective imaging features, and the radiomic features of tumor and peritumoral mesorectum region of patients were extracted from T2WI and ADC images. Spearman's rank correlation coefficient, Mann-Whitney's U test, and the least absolute shrinkage and selection operator were used for feature selection and dimensionality reduction. Logistic regression was used to construct six models. The predictive performance of each model was evaluated by the receiver operating characteristic curve (ROC). The differences of each model were characterized by area under the curve (AUC) via the DeLong test. RESULTS: The AUCs of T2WI, ADC single-sequence radiomics model and multi-sequence radiomics model were 0.73, 0.75, and 0.78, respectively. The multi-sequence multi-regional radiomics model with improved performance was created by combining the radiomics characteristics of the peritumoral mesorectum region with the multi-sequence radiomics model (AUC, 0.87; p < 0.01). The AUC of the clinical model was 0.68, and the MRI-clinical composite evaluation model was obtained by incorporating the clinical data with the multi-sequence multi-regional radiomics features, with an AUC of 0.89. CONCLUSION: The MRI-based multi-sequence multi-regional radiomics model significantly improved the prediction ability of LNM for T3 rectal cancer and could be applied to guide surgical decision-making in patients with T3 rectal cancer.


Assuntos
Metástase Linfática , Imageamento por Ressonância Magnética , Neoplasias Retais , Humanos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Metástase Linfática/diagnóstico por imagem , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Idoso , Valor Preditivo dos Testes , Adulto , Estadiamento de Neoplasias , Radiômica
13.
Front Microbiol ; 15: 1312286, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414777

RESUMO

Over the past decades, many forests have been converted to monoculture plantations, which might affect the soil microbial communities that are responsible for governing the soil biogeochemical processes. Understanding how reforestation efforts alter soil prokaryotic microbial communities will therefore inform forest management. In this study, the prokaryotic communities were comparatively investigated in a secondary Chinese fir forest (original) and a reforested Chinese fir plantation (reforested from a secondary Chinese fir forest) in Southern China. The results showed that reforestation changed the structure of the prokaryotic community: the relative abundances of important prokaryotic families in soil. This might be caused by the altered soil pH and organic matter content after reforestation. Soil profile layer depth was an important factor as the upper layers had a higher diversity of prokaryotes than the lower ones (p < 0.05). The composition of the prokaryotic community presented a seasonality characteristic. In addition, the results showed that the dominant phylum was Acidobacteria (58.86%) with Koribacteraceae (15.38%) as the dominant family in the secondary Chinese fir forest and the reforested plantation. Furthermore, soil organic matter, total N, hydrolyzable N, and NH4+-N were positively correlated with prokaryotic diversity (p < 0.05). Also, organic matter and NO3--N were positively correlated to prokaryotic abundance (p < 0.05). This study demonstrated that re-forest transformation altered soil properties, which lead to the changes in microbial composition. The changes in microbial community might in turn influence biogeochemical processes and the environmental variables. The study could contribute to forest management and policy-making.

14.
Int J Biol Macromol ; 262(Pt 1): 129642, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266838

RESUMO

The objective of this study was to develop an injectable hydrogel based on furfuryl amine-conjugated hyaluronic acid (FA-conj-HA) and evaluate the in vivo anti-4 T1 tumor activity of doxorubicin-loaded hydrogel (DOX@FA-conj-HAgel). The cargo-free hydrogel (FA-conj-HAgel) was fabricated through a Diels-Alder reaction at 37 °C with FA-conj-HA as a gel material and four armed poly(ethylene glycol)2000-maleimide (4-arm-PEG2000-Mal) as a cross-linker. The bio-safety of FA-conj-HAgel were assessed, and the in vivo antitumor activity of DOX@FA-conj-HAgel was also investigated. Many 3D network structures were observed from scanning electron microscope (SEM) photograph, confirming the successful preparation of FA-conj-HAgel. The absence of cytotoxicity from FA-conj-HAgel was proved by the high viability of 4 T1 cells. In vivo bio-safety studies suggested that the obtained FA-conj-HAgel did not induce acute toxicity or other lesions in treated mice, confirming its high bio-safety. The reduced tumor volumes, hematoxylin-eosin staining (H&E), and TdT-mediated dUTP-biotin nick end labeling (TUNEL) analysis indicated the potent in vivo anti-4 T1 tumor effects of DOX@FA-conj-HAgel. In conclusion, the favorable bio-safety and potent antitumor activity of DOX@FA-conj-HAgel highlighted its potential application in oncological therapy.


Assuntos
Hidrogéis , Neoplasias , Camundongos , Animais , Hidrogéis/química , Ácido Hialurônico/química , Reação de Cicloadição , Doxorrubicina/química
15.
Animals (Basel) ; 14(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38929409

RESUMO

Rotavirus is a major causative agent of diarrhoea in children, infants, and young animals around the world. The associated zoonotic risk necessitates the serious consideration of the complete genetic information of rotavirus. A segmented genome makes rotavirus prone to rearrangement and the formation of a new viral strain. Monitoring the molecular epidemiology of rotavirus is essential for its prevention and control. The quantitative RT-PCR targeting the NSP5 gene was used to detect rotavirus group A (RVA) in pig faecal samples, and two pairs of universal primers and protocols were used for amplifying the G and P genotype. The genotyping and phylogenetic analysis of 11 genes were performed by RT-PCR and a basic bioinformatics method. A unique G4P[6] rotavirus strain, designated S2CF (RVA/Pig-tc/CHN/S2CF/2023/G4P[6]), was identified in one faecal sample from a piglet with severe diarrhoea in Guangdong, China. Whole genome sequencing and analysis suggested that the 11 segments of the S2CF strain showed a unique Wa-like genotype constellation and a typical porcine RVA genomic configuration of G4-P[6]-I1-R1-C1-M1-A8-N1-T1-E1-H1. Notably, 4 of the 11 gene segments (VP4, VP6, VP2, and NSP5) clustered consistently with human-like RVAs, suggesting independent human-to-porcine interspecies transmission. Moreover, a unique 344-nt duplicated sequence was identified for the first time in the untranslated region of NSP5. This study further reveals the genetic diversity and potential inter-species transmission of porcine rotavirus.

16.
Chem Mater ; 36(1): 425-438, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38222935

RESUMO

Higher adducts of a fullerene, such as the bis-adduct of PCBM (bis-PCBM), can be used to achieve shallower molecular orbital energy levels than, for example, PCBM or C60. Substituting the bis-adduct for the parent fullerene is useful to increase the open-circuit voltage of organic solar cells or achieve better energy alignment as electron transport layers in, for example, perovskite solar cells. However, bis-PCBM is usually synthesized as a mixture of structural isomers, which can lead to both energetic and morphological disorder, negatively affecting device performance. Here, we present a comprehensive study on the molecular properties of 19 pure bis-isomers of PCBM using a variety of characterization methods, including ultraviolet photoelectron spectroscopy, thermal gravimetric analysis, differential scanning calorimetry, single crystal structure, and (time-dependent) density functional theory calculation. We find that the lowest unoccupied molecular orbital of such bis-isomers can be tuned to be up to 170 meV shallower than PCBM and up to 100 meV shallower than the mixture of unseparated isomers. The isolated bis-isomers also show an electron mobility in organic field-effect transistors of up to 4.5 × 10-2 cm2/(V s), which is an order of magnitude higher than that of the mixture of bis-isomers. These properties enable the fabrication of the highest performing bis-PCBM organic solar cell to date, with the best device showing a power conversion efficiency of 7.2%. Interestingly, we find that the crystallinity of bis-isomers correlates negatively with electron mobility and organic solar cell device performance, which we relate to their molecular symmetry, with a lower symmetry leading to more amorphous bis-isomers, less energetic disorder, and higher dimensional electron transport. This work demonstrates the potential of side chain engineering for optimizing the performance of fullerene-based organic electronic devices.

17.
Rapid Commun Mass Spectrom ; 27(11): 1222-30, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23650035

RESUMO

RATIONALE: Tetrahydroquinoline derivatives possess a broad range of biological activities. Since few studies have been reported concerning metabolites of furo[3,2-c]tetrahydroquinoline- and pyrano[3,2-c]tetrahydroquinoline-derived antitumor agents, the proposed fragmentation mechanisms and their metabolites were investigated in this study. METHODS: The fragmentation pathways of eight furo[3,2-c]tetrahydroquinoline derivatives and six pyrano[3,2-c]tetrahydroquinoline derivatives were analyzed using electrospray ionization tandem mass spectrometry. Hydrogen/deuterium (H/D) exchange reactions were employed to identify the proposed structures of the product ions. In addition, compounds were incubated with human liver microsomes (HLM) at 37 °C for 8 h and the related metabolites were analyzed by liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS). RESULTS: Two protonation modes were summarized and protonation occurring on the oxygen atom of furan or pyran ring could trigger the cleavage of the C-O bond, followed by the elimination of a molecule of water and the substituent at the C2 site, respectively. On the other hand, a proton added to the nitrogen atom may lead to the loss of dihydrofuran or dihydropyran from the protonated molecules. Apart from the general proposed fragmentation pathways above, the variations on the C2 site could result in some specific fragmentation patterns. Further incubating compound B1 with HLM in vitro produced two major metabolites, and the structures were proposed by tandem mass experiments together with the fragmentation mechanisms of these compounds. CONCLUSIONS: These observations play an important role in monitoring and characterization of the presence and metabolites of furo[3,2-c]tetrahydroquinoline and pyrano[3,2-c]tetrahydroquinoline derivatives in complex mixtures, and can provide some applications in further pharmaceutical and therapeutic research.


Assuntos
Antineoplásicos/química , Cromatografia Líquida de Alta Pressão/métodos , Quinolinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Humanos , Microssomos Hepáticos/química , Estrutura Molecular , Peso Molecular
18.
Materials (Basel) ; 16(7)2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37048908

RESUMO

Fullerene-based indoor OPVs, particularly phenyl-C61 butyric acid methyl ester (PCBM), has been regarded as a prospective harvesting indoor light energy source to drive low-power consumption electronic devices such as sensors and IoTs. Due to the low tunability of its inherently spherical structure, the performance of the fullerene-based indoor OPVs seem to hit a bottleneck compared with the non-fullerene materials. Here, we explore the potential application of fullerene derivative bis-PCBM in indoor OPVs, which owns a higher the lowest unoccupied molecular orbital (LUMO) level than PCBM. The results show that when blended with PCDTBT, bis-PCBM devices yield a high VOC of up to 1.05 V and 0.9 V under AM 1.5G illumination and 1000 lx indoor light, compared with the corresponding values of 0.93 V and 0.79 V for PCBM devices. Nevertheless, the disorders in bis-PCBM suppress the JSC and FF and, therefore, result in a lower efficiency compared to PCBM devices. However, the efficiency and stability differences between the two kinds of cells were much reduced under indoor light conditions. After further optimization of the material composition and fabrication process, bis-PCBM could be an alternative to PCBM, offering great potential for indoor OPV with high performance.

19.
Eur J Med Chem ; 260: 115715, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37597438

RESUMO

The purpose of this study was to synthesize DHPD polymers through the conjugation of doxorubicin (DOX) molecules onto poly(ethylene glycol) (PEG) chains via acylhydrazone bonds, and to fabricate pH-responsive DHPD nanoparticles (NPs) for investigation of their biosecurity and in vivo anti-tumor activity. The morphology, size distribution, stability, pH-responsiveness, biosecurity, and in vivo anti-tumor effects of the DHPD NPs were evaluated. Characterization of the DHPD polymers using 1H NMR, FTIR, and Raman spectra confirmed their successful synthesis. The DHPD NPs exhibited a round morphology with an average diameter of 144.4 ± 1.7 nm and a polydispersity index (PDI) of 0.23 ± 0.02. Biosecurity studies indicated that the DHPD NPs were non-toxic to treated mice, and in vitro cell tests demonstrated their ability to be taken up by 4T1 cells. Under the acidic microenvironment of 4T1 cells, the acylhydrazone bonds were cleaved, resulting in increased DOX delivery to tumor cells and improved in vivo anti-tumor effects. Animal experiments confirmed that the DHPD NPs reduced DOX toxicity while enhancing its anti-tumor activity. Furthermore, results from the analysis of γ-interferon (INF-γ), tumor necrosis factor-α (TNF-α), epidermal growth factor (EGF), and vascular endothelial growth factor (VEGF) indicated that the DHPD NPs improved the anti-4T1 tumor effect of DOX, suggesting their potential application in the treatment of breast cancer.


Assuntos
Nanopartículas , Neoplasias , Animais , Camundongos , Fator A de Crescimento do Endotélio Vascular , Doxorrubicina/farmacologia , Polímeros , Concentração de Íons de Hidrogênio , Microambiente Tumoral
20.
Chem Biol Interact ; 384: 110710, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37716421

RESUMO

Poloxamer 188 is a widely used pharmaceutical excipient, which can be found in a variety of drug formulations. In this study, a novel self-assembled nanoplatform was developed for active targeting of folate receptor-overexpressing triple-negative breast cancer. This platform, FPP NPs, was prepared by the retrofitted poloxamer 188 derivatives, resulting in nanoparticles with an appropriate size (< 100 nm), good stability, and satisfactory biocompatibility. Cellular uptake and in vivo distribution studies showed that the FPP NPs had strong tumor cell uptake and active targeting capabilities. Furthermore, docetaxel (DTX) was loaded into FPP NPs in this research. The resulting DTX/FPP NPs exhibited high drug encapsulation efficiency and drug loading capacity, and could rapidly release DTX under slightly acidic conditions, significantly increasing the antitumor activity of the encapsulated drug both in vitro and in vivo. In addition, DTX/FPP NPs could significantly decrease the hepatotoxicity and nephrotoxicity of DTX. Therefore, this drug delivery nanoplatform, based on retrofitted poloxamer 188 with self-assembly properties in aqueous solution and active targeting capabilities to tumors, may provide a promising approach for targeted treatment of triple-negative breast cancer.

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