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1.
Proc Natl Acad Sci U S A ; 119(43): e2213373119, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36256822

RESUMO

The high level of reactive oxygen species (ROS) in the rheumatoid arthritis (RA) microenvironment (RAM) and its persistent inflammatory nature can promote damage to joints, bones, and the synovium. Targeting strategies that integrate effective RAM regulation with imaging-based monitoring could lead to improvements in the diagnosis and treatment of RA. Here, we report the combined use of small interfering RNAs (siRNAsT/I) and Prussian blue nanoparticles (PBNPs) to silence the expression of proinflammatory cytokines TNF-α/IL-6 and scavenge the ROS associated with RAM. To enhance the in vitro and in vivo biological stability, biocompatibility, and targeting capability of the siRNAsT/I and PBNPs, macrophage membrane vesicles were used to prepare biomimetic nanoparticles, M@P-siRNAsT/I. The resulting constructs were found to suppress tumor necrosis factor-α/interleukin-6 expression and overcome the hypoxic nature of RAM, thus alleviating RA-induced joint damage in a mouse model. The M@P-siRNAsT/I of this study could be monitored via near-infrared photoacoustic (PA) imaging. Moreover, multispectral PA imaging without the need for labeling permitted the real-time evaluation of M@P-siRNAsT/I as a putative RA treatment. Clinical microcomputed tomography and histological analysis confirmed the effectiveness of the treatment. We thus suggest that macrophage-biomimetic M@P-siRNAsT/I and their analogs assisted by PA imaging could provide a new strategy for RA diagnosis, treatment, and monitoring.


Assuntos
Artrite Reumatoide , Nanopartículas , Camundongos , Animais , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6 , Espécies Reativas de Oxigênio/metabolismo , Biomimética , Microtomografia por Raio-X , Artrite Reumatoide/metabolismo , Citocinas/metabolismo , RNA Interferente Pequeno/uso terapêutico
2.
J Am Chem Soc ; 146(7): 4620-4631, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38330912

RESUMO

Pancreatic cancer is highly lethal. New diagnostic and treatment modalities are desperately needed. We report here that an expanded porphyrin, cyclo[8]pyrrole (CP), with a high extinction coefficient (89.16 L/g·cm) within the second near-infrared window (NIR-II), may be formulated with an αvß3-specific targeting peptide, cyclic-Arg-Gly-Asp (cRGD), to form cRGD-CP nanoparticles (cRGD-CPNPs) with promising NIR-II photothermal (PT) therapeutic and photoacoustic (PA) imaging properties. Studies with a ring-array PA tomography system, coupled with analysis of control nanoparticles lacking a targeting element (CPNPs), revealed that cRGD conjugation promoted the delivery of the NPs through abnormal vessels around the tumor to the solid tumor core. This proved true in both subcutaneous and orthotopic pancreatic tumor mice models, as confirmed by immunofluorescent studies. In combination with NIR-II laser photoirradiation, the cRGD-CPNPs provided near-baseline tumor growth inhibition through PTT both in vitro and in vivo. Notably, the combination of the present cRGD-CPNPs and photoirradiation was found to inhibit intra-abdominal metastases in an orthotopic pancreatic tumor mouse model. The cRGD-CPNPs also displayed good biosafety profiles, as inferred from PA tomography, blood analyses, and H&E staining. They thus appear promising for use in combined PA imaging and PT therapeutic treatment of pancreatic cancer.


Assuntos
Nanopartículas , Neoplasias Pancreáticas , Técnicas Fotoacústicas , Animais , Camundongos , Pirróis/uso terapêutico , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/terapia , Nanopartículas/química , Tomografia Computadorizada por Raios X , Técnicas Fotoacústicas/métodos , Linhagem Celular Tumoral , Fototerapia
3.
J Am Chem Soc ; 146(21): 14754-14764, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38754363

RESUMO

Lithium-sulfur (Li-S) batteries are highly considered as next-generation energy storage techniques. Weakly solvating electrolyte with low lithium polysulfide (LiPS) solvating power promises Li anode protection and improved cycling stability. However, the cathodic LiPS kinetics is inevitably deteriorated, resulting in severe cathodic polarization and limited energy density. Herein, the LiPS kinetic degradation mechanism in weakly solvating electrolytes is disclosed to construct high-energy-density Li-S batteries. Activation polarization instead of concentration or ohmic polarization is identified as the dominant kinetic limitation, which originates from higher charge-transfer activation energy and a changed rate-determining step. To solve the kinetic issue, a titanium nitride (TiN) electrocatalyst is introduced and corresponding Li-S batteries exhibit reduced polarization, prolonged cycling lifespan, and high actual energy density of 381 Wh kg-1 in 2.5 Ah-level pouch cells. This work clarifies the LiPS reaction mechanism in protective weakly solvating electrolytes and highlights the electrocatalytic regulation strategy toward high-energy-density and long-cycling Li-S batteries.

4.
Anal Chem ; 96(6): 2286-2291, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38289025

RESUMO

The link between inflammation and the evolution of cancer is well established. Visualizing and tracking both tumor proliferation and the associated inflammatory response within a living organism are vital for dissecting the nexus between these two processes and for crafting precise treatment modalities. We report the creation and synthesis of an advanced NIR chemiluminescence probe that stands out for its exceptional selectivity, extraordinary sensitivity at nanomolar concentrations, swift detection capabilities, and broad application prospects. Crucially, this probe has been successfully utilized to image endogenous ONOO- across different inflammation models, including abdominal inflammation triggered by LPS, subcutaneous inflammatory conditions, and tumors grafted onto mice. These findings highlight the significant promise of chemiluminescence imaging in enhancing our grasp of the intricate interplay between cancer and inflammation and in steering the development of potent, targeted therapeutic strategies.


Assuntos
Inflamação , Neoplasias , Animais , Camundongos , Inflamação/diagnóstico por imagem , Luminescência , Neoplasias/diagnóstico por imagem , Corantes Fluorescentes , Ácido Peroxinitroso
5.
J Med Virol ; 96(1): e29393, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38235934

RESUMO

Acute gastroenteritis outbreaks may be caused by the excretion of norovirus (NoV) from asymptomatic individuals. Despite numerous studies involving asymptomatic NoV infection during outbreaks in China, a comprehensive assessment of its role has not been conducted, which is critical for emergency management. Our objective was to assess the prevalence of asymptomatic NoV infection during outbreaks in China. We conducted a comprehensive search of multiple databases, including PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure, China Wanfang, and China Weipu, between January 1, 1997 and June 19, 2023. The retrieved articles and their references underwent screening, which utilized polymerase chain reaction-based assays for the detection of NoV in asymptomatic individuals during outbreaks that occurred in China. The primary summary data were the prevalence of asymptomatic NoV infection in outbreaks. We generated pooled estimates of asymptomatic prevalence in the population as a whole and in subgroups by using random-effect models. Of the 97 articles included, the pooled asymptomatic prevalence of NoV among 5117 individuals in outbreaks was 17.6% (95% confidence interval [CI]: 14.1-21.3). The asymptomatic prevalence of NoV GII (17.1%, 95% CI: 12.9-21.5) was similar to that of NoV GI (22.0%, 95% CI: 12.8-32.4). However, the proportion of asymptomatic individuals involved in NoV GII (57.44%) was significantly higher than that of NoV GI (5.12%), and NoV GII (75.26%) was reported much more frequently than NoV GI (14.43%) in the included articles. Meta-regression analysis of 11 possible influencing factors (geographic region, setting, season, sample type, genotype, transmission route, occupation, age, per capita income, study quality, and cases definition) showed that the source of heterogeneity might be related to the outbreak settings, per capita income, and study quality (p = 0.037, 0.058, and 0.026, respectively). Of particular note was the asymptomatic prevalence peaked in preschoolers (27.8%), afterward, it fell into trough in elementary and junior school children (10.5%), before the second peak located in adults (17.8%), and the elderly (25.2%). Prevalent genotypes reported include GII.4, followed by GII.17, GII.2, GII.3, GII.6, and so forth. The estimated asymptomatic prevalence of NoV during outbreaks in China was as high as 17.6%, with NoV GII dominating. In addition, genetic subtypes of NoV in outbreaks should be detected whenever possible. The role of asymptomatic individuals in NoV outbreaks cannot be ignored. This knowledge will help governments develop public health policies and emergency response strategies for outbreaks, assess the burden, and develop vaccines.


Assuntos
Infecções Assintomáticas , Infecções por Caliciviridae , Humanos , Infecções Assintomáticas/epidemiologia , Infecções por Caliciviridae/epidemiologia , China/epidemiologia , Surtos de Doenças , Fezes , Genótipo , Norovirus , Filogenia
6.
Bioconjug Chem ; 35(5): 674-681, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695582

RESUMO

Aptamers are widely used molecular recognition tools in targeted therapy, but their ability to effectively penetrate deep into solid tumors remains a significant challenge, leading to suboptimal treatment efficacy. Here, we developed a polyfluoroalkyl (PFA) decoration strategy to enhance aptamer recognition, cell internalization, and solid tumor penetration. Our results indicate that PFA with around 11 fluorine atoms significantly improves aptamer internalization both in vitro and in vivo settings. However, we also observed that the use of PFA tags containing 19 and 23 fluorine atoms on aptamers resulted in nonspecific cell anchoring in control cell lines, affecting the specificity of aptamers. Overall, we found that using a chemical modification strategy could enhance the deep tumor penetration ability of aptamers and validate their effectiveness in vivo. This approach has significant practical applications in targeted drug delivery for cancer treatment.


Assuntos
Aptâmeros de Nucleotídeos , Receptores Proteína Tirosina Quinases , Aptâmeros de Nucleotídeos/química , Humanos , Animais , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/metabolismo , Linhagem Celular Tumoral , Camundongos , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Sistemas de Liberação de Medicamentos/métodos
7.
BMC Cancer ; 24(1): 237, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383348

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a common malignant tumor with strong invasiveness and poor prognosis. Previous studies have demonstrated the significant role of USP14 in various solid tumors. However, the role of USP14 in the regulation of HCC development and progression remains unclear. METHODS: We discovered through GEO and TCGA databases that USP14 may play an important role in liver cancer. Using bioinformatics analysis based on the Cancer Genome Atlas (TCGA) database, we screened and identified USP14 as highly expressed in liver cancer. We detected the growth and metastasis of HCC cells promoted by USP14 through clone formation, cell counting kit 8 assay, Transwell assay, and flow cytometry. In addition, we detected the impact of USP14 on the downstream protein kinase B (AKT) and epithelial-mesenchymal transition (EMT) pathways using western blotting. The interaction mechanism between USP14 and HK2 was determined using immunofluorescence and coimmunoprecipitation (CO-IP) experiments. RESULTS: We found that sh-USP14 significantly inhibits the proliferation, invasion, and invasion of liver cancer cells, promoting apoptosis. Further exploration revealed that sh-USP14 significantly inhibited the expression of HK2. Sh-USP14 can significantly inhibit the expression of AKT and EMT signals. Further verification through immunofluorescence and CO-IP experiments revealed that USP14 co-expressed with HK2. Further research has found that USP14 regulates the glycolytic function of liver cancer cells by the deubiquitination of HK2. USP14 regulates the autophagy function of liver cancer cells by regulating the interaction between SQSTM1/P62 and HK2. CONCLUSIONS: Our results indicate that USP14 plays a crucial role in the carcinogenesis of liver cancer. We also revealed the protein connections between USP14, HK2, and P62 and elucidated the potential mechanisms driving cancer development. The USP14/HK2/P62 axis may be a new therapeutic biomarker for the diagnosis and treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo
8.
Brain Behav Immun ; 116: 185-192, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38081434

RESUMO

BACKGROUND: Recent studies have confirmed an association between pain and dementia. Whether musculoskeletal pain in the spine, upper limbs, and lower limbs is associated with dementia risk remains unclear. The longitudinal effect of musculoskeletal pain on dementia risk also remains unclear. AIMS: This work aimed to investigate the association between musculoskeletal pain and dementia risk score. METHODS: We conducted cross-sectional and longitudinal analyses using data from the China Health and Retirement Longitudinal Study. Participants aged 45 years or older were recruited in 2011. A total of 10,759 participants with complete pain information at baseline were eligible for the cross-sectional analysis, and 5,855 were eligible for the longitudinal analyses. We utilized the Rotterdam Study Basic Dementia Risk Model (BDRM) to assess dementia risk. Generalized estimating equations were used to investigate the associations. RESULTS: Compared with participants without persistent musculoskeletal pain, those with persistent musculoskeletal pain (standardized, ß = 0.83; 95 % CI: 0.06, 1.61, p = 0.036), multisite pain (sites≧5; ß = 1.52; 95 % CI: 0.13, 2.91, p = 0.032), neck pain (ß = 2.33; 95 % CI: 0.41, 4.25, p = 0.018), back pain (ß = 2.12; 95 % CI: 0.43, 3.82, p = 0.014), waist pain (ß = 1.09; 95 % CI: 0.07, 2.11, p = 0.037), shoulder pain (ß = 1.74; 95 % CI: 0.46, 3.02, p = 0.008), wrist pain (ß = 2.72; 95 % CI: 0.42, 5.02, p = 0.021), and knee pain (ß = 1.91; 95 % CI: 0.70, 3.13, p = 0.002) had a higher BDRM score during 4 years of follow-up. CONCLUSIONS: Promoting the management of musculoskeletal pain may be beneficial in reducing the dementia risk score.


Assuntos
Demência , Dor Musculoesquelética , Adulto , Humanos , Estudos Longitudinais , Dor Musculoesquelética/epidemiologia , Aposentadoria , Estudos Transversais , Fatores de Risco
9.
Mol Pharm ; 21(4): 1804-1816, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38466359

RESUMO

Neuroinflammation is a significant pathological event involving the neurodegenerative process associated with many neurological disorders. Diagnosis and treatment of neuroinflammation in its early stage are essential for the prevention and management of neurological diseases. Herein, we designed macrophage membrane-coated photoacoustic (PA) probes (MSINPs), with targeting specificities based on naturally existing target-ligand interactions for the early diagnosis of neuroinflammation. The second near-infrared dye, IR1061, was doped into silica as the core and was encapsulated with a macrophage membrane. In vitro as well as in vivo, the MSINPs could target inflammatory cells via the inflammation chemotactic effect. PA imaging was used to trace the MSINPs in a neuroinflammation mouse model and showed a great targeted effect of MSINPs in the prefrontal cortex. Therefore, the biomimetic nanoprobe prepared in this study offers a new strategy for PA molecular imaging of neuroinflammation, which can enhance our understanding of the evolution of neuroinflammation in specific brain regions.


Assuntos
Nanopartículas , Técnicas Fotoacústicas , Animais , Camundongos , Doenças Neuroinflamatórias , Técnicas Fotoacústicas/métodos , Biomimética , Imagem Óptica
10.
Phys Chem Chem Phys ; 26(24): 17223-17231, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38855975

RESUMO

The electronic, optical and photocatalytic properties of GaN/C2N van der Waals heterostructures are investigated using the first-principles theory, and effective regulation through element doping or strain is achieved further. The results show that the GaN/C2N heterostructure exhibits a type-II band alignment with an indirect band gap of 2.25 eV, which benefits photocatalytic water splitting. In this study, both type-I and type-II band alignments can be obtained through doping or strain modulation. Doping with P or As atoms reduces the band gap of the GaN/C2N heterostructure and transforms it to a type-I direct bandgap semiconductor, which makes the doped GaN/C2N heterostructure more suitable for optoelectronic devices. In addition, the GaN/C2N heterostructure retains type-II band alignment and has a decreased band gap under tensile strain (0 to +4%), which is more favorable for photocatalytic water splitting. Compressive strain (0 to -4%) converts the type-II band alignment to type-I, resulting in a wider light absorption range, making the GaN/C2N heterostructure more suitable for optoelectronic devices. These theoretical results are helpful for the design of GaN/C2N vdW heterostructures in the fields of optoelectronic devices and photocatalysts.

11.
J Nanobiotechnology ; 22(1): 224, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702709

RESUMO

Poorly identified tumor boundaries and nontargeted therapies lead to the high recurrence rates and poor quality of life of prostate cancer patients. Near-infrared-II (NIR-II) fluorescence imaging provides certain advantages, including high resolution and the sensitive detection of tumor boundaries. Herein, a cyanine agent (CY7-4) with significantly greater tumor affinity and blood circulation time than indocyanine green was screened. By binding albumin, the absorbance of CY7-4 in an aqueous solution showed no effects from aggregation, with a peak absorbance at 830 nm and a strong fluorescence emission tail beyond 1000 nm. Due to its extended circulation time (half-life of 2.5 h) and high affinity for tumor cells, this fluorophore was used for primary and metastatic tumor diagnosis and continuous monitoring. Moreover, a high tumor signal-to-noise ratio (up to ~ 10) and excellent preferential mitochondrial accumulation ensured the efficacy of this molecule for photothermal therapy. Therefore, we integrated NIR-II fluorescence-guided surgery and intraoperative photothermal therapy to overcome the shortcomings of a single treatment modality. A significant reduction in recurrence and an improved survival rate were observed, indicating that the concept of intraoperative combination therapy has potential for the precise clinical treatment of prostate cancer.


Assuntos
Carbocianinas , Mitocôndrias , Recidiva Local de Neoplasia , Terapia Fototérmica , Neoplasias da Próstata , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Terapia Fototérmica/métodos , Humanos , Animais , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Linhagem Celular Tumoral , Carbocianinas/química , Imagem Óptica/métodos , Camundongos , Cirurgia Assistida por Computador/métodos , Corantes Fluorescentes/química , Camundongos Nus , Camundongos Endogâmicos BALB C , Raios Infravermelhos , Verde de Indocianina/química , Verde de Indocianina/uso terapêutico , Verde de Indocianina/farmacologia
12.
Clin Rehabil ; 38(6): 715-731, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38317586

RESUMO

OBJECTIVE: To review the effectiveness of different physical therapies for acute and sub-acute low back pain supported by evidence, and create clinical recommendations and expert consensus for physiotherapists on clinical prescriptions. DATA SOURCES: A systematic search was conducted in PubMed and the Cochrane Library for studies published within the previous 15 years. REVIEW METHODS: Systematic review and meta-analysis, randomized controlled trials assessing patients with acute and sub-acute low back pain were included. Two reviewers independently screened relevant studies using the same inclusion criteria. The Physiotherapy Evidence Database and the Assessment of Multiple Systematic Reviews tool were used to grade the quality assessment of randomized controlled trials and systematic reviews, respectively. The final recommendation grades were based on the consensus discussion results of the Delphi of 22 international experts. RESULTS: Twenty-one systematic reviews and 21 randomized controlled trials were included. Spinal manipulative therapy and low-level laser therapy are recommended for acute low back pain. Core stability exercise/motor control, spinal manipulative therapy, and massage can be used to treat sub-acute low back pain. CONCLUSIONS: The consensus statements provided medical staff with appliable recommendations of physical therapy for acute and sub-acute low back pain. This consensus statement will require regular updates after 5-10 years.


Assuntos
Dor Lombar , Modalidades de Fisioterapia , Humanos , Dor Lombar/reabilitação , Dor Lombar/terapia , Consenso , Ensaios Clínicos Controlados Aleatórios como Assunto , Feminino , Dor Aguda/terapia , Dor Aguda/reabilitação , Masculino
13.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731482

RESUMO

An efficient palladium-catalyzed carbonylation of aryl fluorosulfates with aryl formates for the facile synthesis of esters was developed. The cross-coupling reactions proceeded effectively in the presence of a palladium catalyst, phosphine ligand, and triethylamine in DMF to produce the corresponding esters in moderate to good yields. Of note, functionalities or substituents, such as nitro, cyano, methoxycarbonyl, trifluoromethyl, methylsulfonyl, trifluoromethoxy, fluoro, chloro, bromo, methyl, methoxy, N,N-dimethyl, and [1,3]dioxolyl, were well-tolerated in the reactions, which could be kept for late-stage modification. The reactions employing readily available and relatively robust aryl fluorosulfates as coupling electrophiles could potentially serve as an attractive alternative to traditional cross-couplings with the use of aryl halides and pseudohalides as substrates.

14.
Molecules ; 29(4)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38398583

RESUMO

Hydroxylation of aryl sulfonium salts could be realized by utilizing acetohydroxamic acid and oxime as hydroxylative agents in the presence of cesium carbonate as a base, leading to a variety of structurally diverse hydroxylated arenes in 47-95% yields. In addition, the reaction exhibited broad functionality tolerance, and a range of important functional groups (e.g., cyano, nitro, sulfonyl, formyl, keto, and ester) could be well amenable to the mild reaction conditions.

15.
J Environ Sci (China) ; 139: 217-225, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38105049

RESUMO

Hexavalent chromium [Cr(VI)] causes serious harm to the environment due to its high toxicity, solubility, and mobility. Ferrihydrites (Fh) are the main adsorbent and trapping agent of Cr(VI) in soils and aquifers, and they usually coexist with silicate (Si), forming Si-containing ferrihydrite (Si-Fh) mixtures. However, the mechanism of Cr(VI) retention by Si-Fh mixtures is poorly understood. In this study, the behaviors and mechanisms of Cr(VI) adsorption onto Si-Fh with different Si/Fe molar ratios was investigated. Transmission electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and other techniques were used to characterize Si-Fh and Cr(VI)-loading of Si-Fh. The results show that specific surface area of Si-Fh increases gradually with increasing Si/Fe ratios, but Cr(VI) adsorption on Si-Fh decreases with increasing Si/Fe ratios. This is because with an increase in Si/Fe molar ratio, the point of zero charge of Si-Fh gradually decreases and electrostatic repulsion between Si-Fh and Cr(VI) increases. However, the complexation of Cr(VI) is enhanced due to the increase in adsorbed hydroxyl (A-OH-) on Si-Fh with increasing Si/Fe molar ratio, which partly counteracts the effect of the electrostatic repulsion. Overall, the increase in the electrostatic repulsion has a greater impact on adsorption than the additional complexation with Si-Fh. Density functional theory calculation further supports this observation, showing the increases in electron variation of bonding atoms and reaction energies of inner spherical complexes with the increase in Si/Fe ratio.


Assuntos
Cromo , Compostos Férricos , Compostos Férricos/química , Cromo/química , Silicatos , Adsorção
16.
Angew Chem Int Ed Engl ; : e202405802, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837569

RESUMO

Solid polymer electrolytes are promising electrolytes for safe and high-energy-density lithium metal batteries. However, traditional ether-based polymer electrolytes are limited by their low lithium-ion conductivity and narrow electrochemical window because of the well-defined and intimated Li+-oxygen binding topologies in the solvation structure. Herein, we proposed a new strategy to reduce the Li+-polymer interaction and strengthen the anion-polymer interaction by combining strong Li+-O (ether) interactions, weak Li+-O (ester) interactions with steric hindrance in polymer electrolytes. In this way, a polymer electrolyte with a high lithium ion transference number (0.80) and anion-rich solvation structure is obtained. This polymer electrolyte possesses a wide electrochemical window (5.5 V versus Li/Li+) and compatibility with both Li metal anode and high-voltage NCM cathode. Li||LiNi0.5Co0.2Mn0.3O2 full cells with middle-high active material areal loading (~7.5 mg cm-2) can stably cycle at 4.5 V. This work provides new insight into the design of polymer electrolytes for high-energy-density lithium metal batteries through the regulation of ion-dipole interactions.

17.
Angew Chem Int Ed Engl ; 63(10): e202318785, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38226740

RESUMO

The cycle life of high-energy-density lithium-sulfur (Li-S) batteries is severely plagued by the incessant parasitic reactions between Li metal anodes and reactive Li polysulfides (LiPSs). Encapsulating Li-polysulfide electrolyte (EPSE) emerges as an effective electrolyte design to mitigate the parasitic reactions kinetically. Nevertheless, the rate performance of Li-S batteries with EPSE is synchronously suppressed. Herein, the sacrifice in rate performance by EPSE is circumvented while mitigating parasitic reactions by employing hexyl methyl ether (HME) as a co-solvent. The specific capacity of Li-S batteries with HME-based EPSE is nearly not decreased at 0.1 C compared with conventional ether electrolytes. With an ultrathin Li metal anode (50 µm) and a high-areal-loading sulfur cathode (4.4 mgS cm-2 ), a longer cycle life of 113 cycles was achieved in HME-based EPSE compared with that of 65 cycles in conventional ether electrolytes at 0.1 C. Furthermore, both high energy density of 387 Wh kg-1 and stable cycle life of 27 cycles were achieved in a Li-S pouch cell (2.7 Ah). This work inspires the feasibility of regulating the solvation structure of LiPSs in EPSE for Li-S batteries with balanced performance.

18.
J Am Chem Soc ; 145(30): 16449-16457, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37427442

RESUMO

Lithium-sulfur (Li-S) batteries afford great promise on achieving practical high energy density beyond lithium-ion batteries. Lean-electrolyte conditions constitute the prerequisite for achieving high-energy-density Li-S batteries but inevitably deteriorates battery performances, especially the sulfur cathode kinetics. Herein, the polarizations of the sulfur cathode are systematically decoupled to identify the key kinetic limiting factor in lean-electrolyte Li-S batteries. Concretely, an electrochemical impedance spectroscopy combined galvanostatic intermittent titration technique method is developed to decouple the cathodic polarizations into activation, concentration, and ohmic parts. Therein, activation polarization during lithium sulfide nucleation emerges as the dominant polarization as the electrolyte-to-sulfur ratio (E/S ratio) decreases, and the sluggish interfacial charge transfer kinetics is identified as the main reason for degraded cell performances under lean-electrolyte conditions. Accordingly, a lithium bis(fluorosulfonyl)imide electrolyte is proposed to decrease activation polarization, and Li-S batteries adopting this electrolyte provide a discharge capacity of 985 mAh g-1 under a low E/S ratio of 4 µL mg-1 at 0.2 C. This work identifies the key kinetic limiting factor of lean-electrolyte Li-S batteries and provides guidance on designing rational promotion strategies to achieve advanced Li-S batteries.

19.
Anal Chem ; 95(35): 13191-13200, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37610431

RESUMO

Chemiluminescent probes have become increasingly popular in various research areas including precise tumor imaging and immunofluorescence analysis. Nevertheless, previously developed chemiluminescence probes are mainly limited to studying oxidation reaction-associated biological events. This study presents the first example of bioimaging applicable bicyclic dioxetane chemiluminescent probes with tunable emission wavelengths that range from 525 to 800 nm. These newly developed probes were able to detect the analytes of ß-Gal, H2O2, and superoxide with high specificity and a limit of detection of 77 mU L-1, 96, and 28 nM, respectively. The bioimaging application of the probes was verified in ovarian and liver cancer cells and macrophage cells, allowing the detection of the content of ß-Gal, H2O2, and superoxide inside the cells. The high specificity allowed us to image the xenografted tumor in mice. We expect that our probes will receive extensive applications in recording complex biomolecular events using noninvasive imaging techniques.


Assuntos
Peróxido de Hidrogênio , Superóxidos , Animais , Camundongos , Diagnóstico por Imagem , Linhagem Celular , Xenoenxertos
20.
Small ; 19(8): e2205315, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36470676

RESUMO

In recent years, the rapid development of modern society is calling for advanced energy storage to meet the growing demands of energy supply and generation. As one of the most promising energy storage systems, secondary batteries are attracting much attention. The electrolyte is an important part of the secondary battery, and its composition is closely related to the electrochemical performance of the secondary batteries. Lithium-ion battery electrolyte is mainly composed of solvents, additives, and lithium salts, which are prepared according to specific proportions under certain conditions and according to the needs of characteristics. This review analyzes the advantages and current problems of the liquid electrolytes in lithium-ion batteries (LIBs) from the mechanism of action and failure mechanism, summarizes the research progress of solvents, lithium salts, and additives, analyzes the future trends and requirements of lithium-ion battery electrolytes, and points out the emerging opportunities in advanced lithium-ion battery electrolytes development.

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