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1.
Diabetes Metab Syndr Obes ; 17: 1563-1573, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38601038

RESUMEN

Introduction: Diabetes and obesity are momentous risk factors threatening people's lives and health. Currently available incretin analogue glucagon-like peptide 1 (GLP-1) possesses huge hypoglycemic effect with the unsatisfactory effect of weight loss. Co-agonists targeting GLP-1R plus glucagon receptor (GCGR) or gastric inhibitory polypeptide receptor (GIPR) show synergistic benefits in glycaemic control and weight loss. Here, we describe a novel dual GIP and GLP-1 receptor agonist, DR10627, and performed a preclinical assessment of it. Methods: The agonistic ability of DR10627 was indirectly assessed by inducing cAMP accumulation in Chinese hamster ovary (CHO) cells transfected with GLP-1R or GIPR in vitro. The plasma pharmacokinetics of DR10627 were analysed in cynomolgus monkeys. The OGTTs were performed in Sprague­Dawley (SD) rats. The glucose lowering effects were evaluated by repeated administration of DR10627 in diabetic (db/db) mice for 4 weeks. The effects of anti-obesity and improving metabolism of DR10627 were evaluated by repeated administration of DR10627 in diet-induced obesity (DIO) mice for 57 days. Results: DR10627 had the capacity to activate both GLP-1R and GIPR in vitro. The terminal half-life of DR10627 was found to be approximately 4.19-5.8 h in cynomolgus monkeys. DR10627 had a great improvement in oral glucose tolerance in SD rats. Moreover, DR10627 had a potent glucose-lowering effect in db/db mice, and the hypoglycemic effect of 18 nmol/kg DR10627 was better than that of 50 nmol/kg liraglutide. In addition, 10 and 30 nmol/kg DR10627 possessed the ability of potentiating the weight-loss, lipid-lowing efficacy and improving metabolism to a greater extent than 80 nmol/kg liraglutide. Conclusion: Preclinical assessment demonstrated that administration of DR10627 resulted in glucose lowering in SD rats and db/db mice, and substantial body weight reduction and metabolism improvement in DIO mice. DR10627 is a promising agent deserving further investigation for the treatment of type 2 diabetes and obesity.

2.
Cancer Immunol Immunother ; 73(5): 82, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38554200

RESUMEN

BACKGROUND: Claudin 18.2 (CLDN18.2) is a highly anticipated target for solid tumor therapy, especially in advanced gastric carcinoma and pancreatic carcinoma. The T cell engager targeting CLDN18.2 represents a compelling strategy for enhancing anti-cancer efficacy. METHODS: Based on the in-house screened anti-CLDN18.2 VHH, we have developed a novel tri-specific T cell engager targeting CLDN18.2 for gastric and pancreatic cancer immunotherapy. This tri-specific antibody was designed with binding to CLDN18.2, human serum albumin (HSA) and CD3 on T cells. RESULTS: The DR30318 demonstrated binding affinity to CLDN18.2, HSA and CD3, and exhibited T cell-dependent cellular cytotoxicity (TDCC) activity in vitro. Pharmacokinetic analysis revealed a half-life of 22.2-28.6 h in rodents and 41.8 h in cynomolgus monkeys, respectively. The administration of DR30318 resulted in a slight increase in the levels of IL-6 and C-reactive protein (CRP) in cynomolgus monkeys. Furthermore, after incubation with human PBMCs and CLDN18.2 expressing cells, DR30318 induced TDCC activity and the production of interleukin-6 (IL-6) and interferon-gamma (IFN-γ). Notably, DR30318 demonstrated significant tumor suppression effects on gastric cancer xenograft models NUGC4/hCLDN18.2 and pancreatic cancer xenograft model BxPC3/hCLDN18.2 without affecting the body weight of mice.


Asunto(s)
Neoplasias Pancreáticas , Neoplasias Gástricas , Humanos , Ratones , Animales , Linfocitos T , Interleucina-6 , Macaca fascicularis/metabolismo , Neoplasias Pancreáticas/terapia , Neoplasias Gástricas/patología , Inmunoterapia , Claudinas/metabolismo
3.
Int Immunopharmacol ; 130: 111698, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38377856

RESUMEN

Immunosuppressive pathways in the tumor microenvironment (TME) are inextricably linked to tumor progression. Mono-therapeutics of immune checkpoint inhibitors (ICIs, e.g. antibodies against programmed cell death protein-1/programmed cell death ligand-1, PD-1/PD-L1) is prone to immune escape while combination therapeutics tends to cause high toxicity and side effects. Therefore, using multi-functional molecules to target multiple pathways simultaneously is becoming a new strategy for cancer therapies. Here, we developed a trifunctional fusion protein, DR30206, composed of Bevacizumab (an antibody against VEGF), and a variable domain of heavy chain of heavy chain antibody (VHH) against PD-L1 and the extracellular domain (ECD) protein of TGF-ß receptor II (TGF-ß RII), which are fused to the N- and C-terminus of Bevacizumab, respectively. The original intention of DR30206 design was to enhance the immune responses pairs by targeting PD-L1 while inhibiting VEGF and TGF-ß in the TME. Our data demonstrated that DR30206 exhibits high antigen-binding affinities and efficient blocking capabilities, the principal drivers of efficacy in antibody therapy. Furthermore, the capability of eliciting antibody-dependent cellular cytotoxicity (ADCC) and mixed lymphocyte reaction (MLR) provides a greater possibility to enhance the immune response. Finally, in vivo experiments showed that the antitumor activity of DR30206 was superior to those of monoclonal antibody of PD-L1 or VEGF, PD-L1 and TGF-ß bispecific antibody or the combination inhibition of PD-L1 and VEGF. Our findings suggest there is a great potential for DR30206 to become a therapeutic for the treatment of multiple cancer types, especially lung cancer, colon adenocarcinoma and breast carcinoma.


Asunto(s)
Adenocarcinoma , Neoplasias del Colon , Humanos , Factor A de Crecimiento Endotelial Vascular/genética , Factor de Crecimiento Transformador beta , Antígeno B7-H1 , Bevacizumab/farmacología , Microambiente Tumoral
5.
Front Immunol ; 14: 1184395, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37483630

RESUMEN

Introduction: Bruton tyrosine kinase inhibitor (BTKi) has demonstrated substantial efficacy in treating B-cell lymphoproliferative diseases (BLPD). Nonetheless, the significant discontinuation rates due to toxicity or financial reasons cannot be overlooked. In China, empirical evidence on the usage of BTKi remains scarce. Methods: To address this, a retrospective cohort study was conducted focused on 673 Chinese patients with BLPD who underwent at least one month of BTKi therapy. Results: Median age at BTKi initiation was 60 years. The median duration on BTKi treatment of the whole cohort was 36.4 months. The median post-BTK survival was not reach. BTKi-based treatment was permanently discontinued in 288 (43.8%) patients during follow-up, mostly attributed to progressive disease. Within the first 6 months of BTKi treatment, 76 patients (26.3%) had early treatment discontinuation. Patients with early discontinuation had extreme worse outcome with a median post-discontinuation survival of only 6.9 months. On multivariate analysis, withdrawal BTKi by toxicity and withdrawal BTKi within 6 months retained to be independent predictors of post-BTK survival, after taking account of the response depth, lines of therapy and baseline cytogenetics including 17p deletion. The decision between BTKi monotherapy and combination therapy, along with the preference for first or second-generation BTKi, exerted no significant impact on survival. Discussions: These observations contribute valuable real-world insights into the utilization of BTKi in China. We concluded that BTKi is an effective and well-tolerated treatment for long-term use in Chinese patient population. However, it is imperative to stress that a proportion of patients discontinue BTKi early, leading to suboptimal outcomes. This study underscores the importance of adherence to BTKi therapy for improved clinical outcomes in real-world patients.


Asunto(s)
Leucemia Linfocítica Crónica de Células B , Trastornos Linfoproliferativos , Humanos , Persona de Mediana Edad , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Estudios Retrospectivos , Linfocitos B , Trastornos Linfoproliferativos/tratamiento farmacológico , Terapia Combinada
6.
Front Immunol ; 14: 1171539, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37234167

RESUMEN

Introduction: Minimal residual disease (MRD) has been recognized as an important prognostic factor of survival in patients with hematological malignancies. However, the prognostic value of MRD in Waldenström macroglobulinemia (WM) remains unexplored. Methods: We analyzed 108 newly diagnosed WM patients receiving systematic therapy and assessed for MRD by multiparameter flow cytometry (MFC) using bone marrow samples. Results: Of the total patients, 34 (31.5%) achieved undetectable MRD (uMRD). A hemoglobin level of >115 g/L (P=0.03), a serum albumin level of >35 g/L (P=0.01), a ß2-MG level of ≤3 mg/L (P=0.03), and a low-risk International Prognostic Scoring System for WM (IPSSWM) stage (P<0.01) were associated with a higher rate of uMRD. Improvements in monoclonal immunoglobulin (P<0.01) and hemoglobin (P=0.03) levels were more evident in uMRD patients compared with that in MRD-positive patients. The 3-year progression-free survival (PFS) was better in uMRD patients compared with that in MRD-positive patients (96.2% vs. 52.8%; P=0.0012). Landmark analysis also showed that uMRD patients had better PFS compared with MRD-positive patients after 6 and 12 months. Patients who achieved partial response (PR) and uMRD had a 3-year PFS of 100%, which was significantly higher than that of patients with MRD-positive PR (62.6%, P=0.029). Multivariate analysis showed that MRD positivity was an independent factor of PFS (HR: 2.55, P=0.03). Moreover, the combination of the 6th International Workshop on WM assessment (IWWM-6 Criteria) and MRD assessment had a higher 3-year AUC compared with the IWWM-6 criteria alone (0.71 vs. 0.67). Discussion: MRD status assessed by MFC is an independent prognostic factor for PFS in patients with WM, and its determination could improve the precision of response evaluation, especially in patients who achieved PR.


Asunto(s)
Macroglobulinemia de Waldenström , Humanos , Macroglobulinemia de Waldenström/diagnóstico , Neoplasia Residual/diagnóstico , Pronóstico , Supervivencia sin Progresión
7.
Nurs Open ; 10(9): 5827-5837, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37219069

RESUMEN

AIM: This study aimed to explore the relationship between nurses' occupational exposure to antineoplastic agents and adverse pregnancy outcomes. DESIGN: Meta-analysis. METHODS: Data were retrieved from studies published before April 2022 in PubMed, the Cochrane Library, the Web of Science, Embase databases, the China National Knowledge Infrastructure (CNKI), China Biology Medicine disc (CBM), China Science and Technology Journal databases (VIP) and Wan Fang databases (WF). Stata MP (Version 17.0) was used to conduct this meta-analysis. RESULTS: The current evidence shows that occupational exposure to antineoplastic agents increases nurses' risk of spontaneous abortions, stillbirths, and congenital abnormalities. It is necessary to pay attention to occupational exposures caused by antineoplastic agents, especially for female nurses of reproductive age. Managers should take timely and effective countermeasures to ensure their occupational safety and reduce the risk of adverse pregnancy outcomes.


Asunto(s)
Antineoplásicos , Enfermeras y Enfermeros , Exposición Profesional , Humanos , Femenino , Embarazo , Resultado del Embarazo , Proyectos de Investigación , Exposición Profesional/efectos adversos , Antineoplásicos/efectos adversos
8.
Int Arch Occup Environ Health ; 96(6): 785-796, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37079056

RESUMEN

OBJECTIVE: Antineoplastic drugs (ADs) are widely used in clinical practice and have been demonstrated to be effective in treating malignant tumors. However, they carry a risk of cytogenotoxicity for healthcare workers. Studies have reported that genotoxic biomarkers can be applied to assess the occupational health status of healthcare workers at an early stage, but results of different studies are variable. The objectives of the review were examine the association between long-term exposure to ADs and cytogenetic damage to healthcare workers. METHODS: We systematically reviewed studies between 2005 and 2021 using PubMed, Embase and Web of Science databases that used cytogenetic biomarkers to assess occupational exposure to ADs in healthcare workers. We used RevMan5.4 to analyze the tail length parameters of the DNA, frequency of the chromosomal aberrations, sister chromatid exchanges and micronuclei. A total of 16 studies were included in our study. The studies evaluate the quality of the literature through the Agency for Healthcare Research and Quality. RESULTS: The results revealed that under the random-effects model, the estimated standard deviation was 2.37 (95% confidence interval [CI] 0.92-3.81, P = 0.001) for the tail length parameters of the DNA, 1.48 (95% CI 0.71-2.25, P = 0.0002) for the frequency of chromosomal aberrations, 1.74 (95% CI 0.49-2.99, P = 0.006) for the frequency of sister chromatid exchanges and 1.64 (95% CI 0.83-2.45, P < 0.0001) for the frequency of micronuclei. CONCLUSIONS: The results indicate that there is a significant association between occupational exposure to ADs and cytogenetic damage, to which healthcare workers should be alerted.


Asunto(s)
Antineoplásicos , Exposición Profesional , Humanos , Antineoplásicos/efectos adversos , Aberraciones Cromosómicas/inducido químicamente , Personal de Salud , Exposición Profesional/efectos adversos , Biomarcadores , Intercambio de Cromátides Hermanas , Análisis Citogenético
9.
Mol Ther Oncolytics ; 27: 305-314, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36570796

RESUMEN

Claudin 18.2 (CLDN18.2) is an emerging target for the treatment of gastric cancers. We aim to develop tracers to image the expression of CLDN18.2. A humanized nanobody targeting CLDN18.2 (clone hu19V3) was produced and labeled with 68Ga, 64Cu, and 18F. The tracers were investigated in subcutaneous and metastatic models established using two different mouse types (nude and Balb/c mice) and two different cell lines (CHO-CLDN18.2 and CT26-CLDN18.2). Gastric cancer patient-derived xenograft (PDX) models were further established for validation experiments. Three novel CLDN18.2-targeted tracers (i.e., [68Ga]Ga-NOTA-hu19V3, [64Cu]Cu-NOTA-hu19V3, and [18F]F-hu19V3) were developed with good radiochemical yields and excellent radiochemical purities. [68Ga]Ga-NOTA-hu19V3 immuno-positron emission tomography (immunoPET) rapidly delineated subcutaneous CHO-CLDN18.2 lesions and CT26-CLDN18.2 tumors, as well as showing excellent diagnostic value in PDX models naturally expressing CLDN18.2. While [68Ga]Ga-NOTA-hu19V3 had high kidney accumulation, [64Cu]Cu-NOTA-hu19V3 showed reduced kidney accumulation and improved image contrast at late time points. Moreover, [18F]F-hu19V3 was developed via click chemistry reaction under mild conditions and precisely disseminated CHO-CLDN18.2 lesions in the lungs. Furthermore, region of interest analysis, biodistribution study, and histopathological staining results correlated well with the in vivo imaging results. Taken together, immunoPET imaging with the three tracers can reliably visualize CLDN18.2 expression.

10.
Environ Sci Technol ; 56(23): 17153-17165, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36242560

RESUMEN

Dermal penetration potentials of titanium dioxide nanoparticles (TiO2 NPs) may be affected by aggregation upon contact with sweat. This study investigated the aggregation kinetics of three TiO2 NPs in thirty human sweat samples and four artificial sweat standards. Effects of particle concentration, sweat type, and inorganic (sodium chloride, disodium hydrogen phosphate, and sodium dihydrogen phosphate) and organic (l-histidine, lactic acid, and urea) constituents were examined. Three TiO2 NPs remained colloidally stable in >20/30 human sweat samples and showed significant negative correlations (P < 0.01) between aggregation rates and |zeta potentials|. They aggregated rapidly over 20 min to >750 nm in three artificial sweat standards, while remained more stable in the International-Standard-Organization-pH-5.5 standard. Aggregation behaviors of three TiO2 NPs mostly followed the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, allowing for determining their critical coagulation concentrations in inorganic constituents (15-491 mM) and Hamaker constants (3.3-7.9 × 10-21 J). Higher concentrations of particles, inorganic constituents, and l-histidine destabilized three TiO2 NPs, whereas urea inhibited aggregation. Three TiO2 NPs adsorbed organic sweat constituents via complexation with amino or carboxyl groups, with isotherms following the Langmuir model. Correlation analyses further suggested that the adsorbed organic constituents may stabilize three TiO2 NPs against aggregation in sweat by steric hindrance.


Asunto(s)
Nanopartículas , Sudor , Humanos , Histidina , Titanio , Cinética , Urea
11.
Front Immunol ; 13: 885424, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35837391

RESUMEN

Claudin 18.2 (CLDN18.2), a tight junction (TJ) family protein controlling molecule exchange between cells, is frequently over-expressed in gastric cancer, pancreatic adenocarcinomas and in a fraction of non-small cell lung cancer cases. The tumor properties indicate that CLDN18.2 could be an attractive drug target for gastric and pancreatic cancers. In this study, we present effective strategies for developing anti-CLDN18.2 therapeutic candidates, based on variable domain of heavy chain of heavy chain antibodies (VHHs). CLDN18.2-specific VHHs were isolated by panning a phage display library from an alpaca immunized with a stable cell line highly expressing CLDN18.2. Humanized VHHs fused with human IgG1 Fc, as potential therapeutic candidates, exhibited desirable binding specificity and affinity to CLDN18.2. In vitro experiments showed that hu7v3-Fc was capable of eliciting both antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) on CLDN18.2 positive tumor cells. In the mouse xenograft model, the anti-tumor efficacy of hu7v3-Fc was significantly more potent than Zolbetuximab, the benchmark anti-CLDN18.2 monoclonal antibody. Moreover, in vivo biodistribution using zirconium-89 (89Zr) labeled antibodies demonstrated that hu7v3-Fc (89Zr-hu7v3-Fc) exhibited a better tumor penetration and a faster tumor uptake than Zolbetuximab (89Zr-Zolbetuximab), which might be attributed to its smaller size and higher affinity. Taken together, anti-CDLN18.2 hu7v3-Fc is a promising therapeutic agent for human CLDN18.2 positive cancers. Furthermore, hu7v3 has emerged as a potential module for novel CLDN18.2 related therapeutics.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Neoplasias Gástricas , Animales , Claudinas/metabolismo , Humanos , Ratones , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo , Distribución Tisular
12.
Mikrochim Acta ; 187(4): 203, 2020 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-32146599

RESUMEN

A new portable molecular imprinting polymer (MIP)-SERS nanoprobe is fabricated by a convenient electrochemical method. Single-layered MoS2 is electrochemically reduced on a screen-printed electrode as the scaffold. Functional monomers o-phenylenediamine (oPD), template theophylline (THP), and SERS-active Au nanoparticles (AuNPs) are then one-step electropolymerized on the scaffold. The morphology of the nanoprobe is found to be a three-dimensional and porous structure. The abundant AuNPs with the size of 45~50 nm are trapped within the growing MIP instead of being confined to the surface. The thickness of MIP film is calculated to 25.1 nm. The nanoprobe displays a strong SERS effect for THP using 532 nm as excitation wavelength with a detection limit (LOD) of 0.01 nM. The SERS peak intensity at 1487 cm-1 increases linearly with the concentration of THP in the range 0.1 nM to 0.1 mM. After the template is removed, the imprint-removed nanoprobe is generated for selective binding of THP. The re-binding kinetics study implies the portable MIP-SERS nanoprobe can reach the adsorption equilibrium within 8 min. This nanoprobe exhibits low SERS interference for structural analogues theobromine (THB) and caffeine (CAF). The nanoprobe was employed to THP determination in tea drink samples, with recoveries ranging from 99.0 to 102.0% and relative standard deviations of < 5.0%. Graphical abstractSchematic representation of a portable molecular imprinting SERS nanoprobe used for selective and sensitive theophylline recognition. The nanoprobe is fabricated by one-step electropolymerized o-phenylenediamine (oPD), theophylline, and electroreduced Au nanoparticles (AuNPs) on reduced MoS2 (rMoS2) modified screen-printed electrode (SPE).


Asunto(s)
Técnicas Biosensibles , Disulfuros/química , Técnicas Electroquímicas , Impresión Molecular , Sondas Moleculares/química , Molibdeno/química , Teofilina/análisis , Nanopartículas/química , Oxidación-Reducción , Espectrometría Raman
13.
ACS Appl Mater Interfaces ; 12(11): 12982-12989, 2020 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-32078288

RESUMEN

Three-dimensional (3D) layered tin oxide quantum dots/graphene framework (SnO2 QDs@GF) were designed through anchoring SnO2 QD on the graphene surface under the hydrothermal reaction. SnO2 QDs@GF have a 3D skeleton with a large number of mesopores and ultrasmall SnO2 QDs with a large surface area. The unique design of this structure improves the specific area and promotes ion transport. The mechanically strong SnO2 QDs@GF can directly be used as the anode of lithium-ion batteries (LIBs); it displays a high reversible capacity (1300 mA h g-1 at 100 mA g-1), excellent rate performance (642 mA h g-1 at 2000 mA g-1), and superior cyclic stability (when the current density is 10 A g-1, the capacity loss is less than 2% after 5000 cycles). This novel synthetic method can further be expanded for the production of other quantum dots/graphene composites with a 3D structure as high-performance electrodes for LIBs.

14.
RSC Adv ; 10(15): 8729-8734, 2020 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-35496540

RESUMEN

Organic carbonyl polymers have been gradually used as the cathode in lithium-ion batteries (LIB). However, there are some limits in most organic polymers, such as low reversible capacity, poor rate performance, cycle instability, etc., due to low electrochemical conductivity. To mitigate the limits, we propose a strategy based on polyimide (PI)/graphene electroactive materials coated with reduced graphene oxide to prepare a flexible film (G@PI/RGO) by solvothermal and vacuum filtration processes. As a flexible cathode for LIB, it provides a reversible capacity of 198 mA h g-1 at 30 mA g-1 and excellent rate performance of 100 mA h g-1 at high current densities of 6000 mA g-1, and even a super long cycle performance (2500 cycles, 70% capacity retention). The excellent performance results in a special layer structure in which the electroactive PI was anchored and coated by the graphene. The present synthetic method can be further applied to construct other high-performance organic electrodes in energy storage.

15.
Chem Asian J ; 13(24): 3859-3864, 2018 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-30457222

RESUMEN

A nitrogen-doped carbon layer coating on a 3D graphene framework (NCL@GF) was produced by the in-situ polymerization of a uniform polyimide layer on the graphene framework surface and a carbonization process. The NCL@GF exhibited a 3D macroporous structure with uniform N-doped porous carbon layers and a high 5.4 at. % nitrogen content, which not only effectively enhanced the active sites but also facilitated fast ion and electron transport in the 3D pathways. Consequently, the NCL@GF as the anode of a sodium-ion battery (SIB) exhibited a discharge capacity of 357 mAh g-1 at 0.1 A g-1 after 200 cycles, a remarkable rate capability with a capacity of 122 mAh g-1 at 8 A g-1 , and a super long cycle life with a capacity retention of 70 % capacity after 2500 cycles at 0.5 A g-1 . Such performance is superior to that of previously reported carbon or graphene-based composites.

16.
Small ; 14(13): e1703969, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29363874

RESUMEN

The designable structure with 3D structure, ultrathin 2D nanosheets, and heteroatom doping are considered as highly promising routes to improve the electrochemical performance of carbon materials as anodes for lithium-ion batteries. However, it remains a significant challenge to efficiently integrate 3D interconnected porous frameworks with 2D tunable heteroatom-doped ultrathin carbon layers to further boost the performance. Herein, a novel nanostructure consisting of a uniform ultrathin N-doped carbon layer in situ coated on a 3D graphene framework (NC@GF) through solvothermal self-assembly/polymerization and pyrolysis is reported. The NC@GF with the nanosheets thickness of 4.0 nm and N content of 4.13 at% exhibits an ultrahigh reversible capacity of 2018 mA h g-1 at 0.5 A g-1 and an ultrafast charge-discharge feature with a remarkable capacity of 340 mA h g-1 at an ultrahigh current density of 40 A g-1 and a superlong cycle life with a capacity retention of 93% after 10 000 cycles at 40 A g-1 . More importantly, when coupled with LiFePO4 cathode, the fabricated lithium-ion full cells also exhibit high capacity and excellent rate and cycling performances, highlighting the practicability of this NC@GF.

17.
ChemSusChem ; 10(17): 3419-3426, 2017 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-28722277

RESUMEN

Small conjugated carbonyl compounds are intriguing candidates for organic electrode materials because of their abundance, high theoretical capacity, and adjustable molecular structure. However, their dissolution in aprotic electrolytes and poor conductivity eclipse them in terms of practical capacity, cycle life, and rate capability. Herein, we report a foldable and binder-free nanocomposite electrode consisting of 2-aminoanthraquinone (AAQ) nanowires wrapped within the 3 D graphene framework, which is prepared through antisolvent crystallization followed by a facile chemical reduction and selfassembly process. The nanocomposite exhibited a very high capacity of 265 mA h g-1 at 0.1 C for AAQ, realizing 100 % utilization of active material. Furthermore, the nanocomposite shows superior cycling stability (82 % capacity retention after 200 cycles at 0.2 C and 76 % capacity retention after 1000 cycles at 0.4 C) and excellent rate performance (153 mA h g-1 at 5 C). Particularly, the nanocomposite can deliver the highest capacity of 165 mA h g-1 among all reported anthraquinone- and anthraquinone-analogues-based electrodes per mass of the whole electrode, which is essential for practical application. Such outstanding electrochemical performance could be largely attributed to the wrapping structure of the flexible composite, which provides both conductivity and structural integrity.


Asunto(s)
Antraquinonas/química , Suministros de Energía Eléctrica , Grafito/química , Litio/química , Nanotecnología/métodos , Nanocables/química , Electrodos , Modelos Moleculares , Conformación Molecular
18.
ACS Appl Mater Interfaces ; 9(18): 15549-15556, 2017 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-28425698

RESUMEN

Polymer cathode materials are promising alternatives to inorganic counterparts for both lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) due to their high theoretical capacity, adjustable molecular structure, and strong adaptability to different counterions in batteries, etc. However, they suffer from poor practical capacity and low rate capability because of their intrinsically poor conductivity. Herein, we report the synthesis of self-assembled graphene/poly(anthraquinonyl sufide) (PAQS) composite aerogel (GPA) with efficient integration of a three-dimensional (3D) graphene framework with electroactive PAQS particles via a novel dispersion-assembly strategy which can be used as a free-standing flexible cathode upon mechanical pressing. The entire GPA cathode can deliver the highest capacity of 156 mAh g-1 at 0.1 C (1 C = 225 mAh g-1) with an ultrahigh utilization (94.9%) of PAQS and exhibits an excellent rate performance with 102 mAh g-1 at 20 C in LIBs. Furthermore, the flexible GPA film was also tested as cathode for SIBs and demonstrated a high-rate capability with 72 mAh g-1 at 5 C and an ultralong cycling stability (71.4% capacity retention after 1000 cycles at 0.5 C) which has rarely been achieved before. Such excellent electrochemical performance of GPA as cathode for both LIBs and SIBs could be ascribed to the fast redox kinetics and electron transportation within GPA, resulting from the interconnected conductive framework of graphene and the intimate interaction between graphene and PAQS through an efficient wrapping structure. This approach opens a universal way to develop cathode materials for powerful batteries with different metal-based counter electrodes.

19.
Phys Chem Chem Phys ; 18(46): 31361-31377, 2016 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-27845454

RESUMEN

The increasing demand for energy and growing concerns for environmental issues are promoting the development of organic electrode materials. Among these, conjugated carbonyl compounds (CCCs) represent one of the most attractive and promising candidates for sustainable and eco-benign energy storage devices in the coming future. However, most of the current compounds suffer from dissolution in organic electrolytes and low electronic conductivity, which result in severe capacity decay and poor rate performance. Recently, researchers have achieved considerable progress by introducing electroactive carbonyl compounds into carbon nanomaterials. This perspective provides an overview of the up-to-date development of these nanocomposites in metal ion batteries (lithium-ion batteries or sodium-ion batteries) and supercapacitors (SCs), including the synthesis, performance improvement and applications. We mainly focus on carbon nanotubes (CNTs), graphene and mesoporous carbon (MC) as carbon nanomaterials because of their high specific surface area, good conductivity, electrochemical stability and favourable interaction with conjugated carbonyl compounds. This strategy opens up new possibilities to realize cost-effective, sustainable and versatile energy storage devices.

20.
Chem Asian J ; 11(8): 1194-8, 2016 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-26593877

RESUMEN

A three-dimensional polymeric carbon nitride/graphene framework (CN/GF) was fabricated by the ionic self-assembly of graphene oxide and protonated polymeric carbon nitride nanosheets. As the cathode material in lithium-ion batteries, CN/GF showed an excellent reversible capacity of 184 mA h g(-1) at 0.05 A g(-1) for 150 cycles and maintained the capacity of 60 mA h g(-1) at 5 A g(-1) .

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