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1.
Small ; 20(3): e2304784, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37699758

RESUMO

Twins in crystal defect, one of the significant factors affecting the physicochemical properties of semiconductor materials, are applied in catalytic conversion. Among the catalysts serving for photocatalytic water splitting, Zn1- x Cdx S has become a hot-point due to its adjustable energy band structure. Via limiting mass transport to control the release rate of anions/cations, twin Zn1- x Cdx S solid solution is prepared successfully, which lays a foundation for the construction of other twin crystals in the future. On twin Zn1- x Cdx S, water tends to be dissociated after being adsorbed by Zn2+ /Cd2+ at twin boundary, then the fast-moving electrons at twin boundary quickly combine with the protons already attached to S2- to form hydrogen. According to the theoretical calculation, not only the intracrystalline electron mobility, but also the extracrystalline capacity of water-adsorption/dissociation and proton-adsorption on the twin boundary are superior to those of the counterpart plane in defect-free phase. The synthetic twin Zn1- x Cdx S apparent quantum efficiency of photocatalysis water splitting for hydrogen reached 82.5% (λ = 420 nm). This research opens up an avenue to introduce twins in crystals and it hopes to shed some light on photocatalysis.

2.
J Colloid Interface Sci ; 659: 21-30, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38157723

RESUMO

Lithium metal is an attractive and promising anode material due to its high energy density and low working potential. However, the uncontrolled growth of lithium dendrites during repeated plating and stripping processes hinders the practical application of lithium metal batteries, leading to low Coulombic efficiency, poor lifespan, and safety concerns. In this study, we synthesized highly lithiophilic and conductive Ag nanoparticles decorated on SiO2 nanospheres to construct an optimized lithium host for promoting uniform Li deposition. The Ag nanoparticles not only act as lithiophilic sites but also provide high electrical conductivity to the Ag@SiO2@Ag anode. Additionally, the SiO2 layer serves as a lithiophilic nucleation agent, ensuring homogeneous lithium deposition and suppressing the growth of lithium dendrites. Theoretical calculations further confirm that the combination of Ag nanoparticles and SiO2 effectively enhances the adsorption ability of Ag@SiO2@Ag with Li+ ions compared to pure Ag and SiO2 materials. As a result, the Ag@SiO2@Ag coating, with its balanced lithiophilicity and conductivity, demonstrates excellent electrochemical performance, including high Coulombic efficiency, low polarization voltage, and long cycle life. In a full lithium metal cell with LiFePO4 cathode, the Ag@SiO2@Ag anode exhibits a high capacity of 133.1 and 121.4 mAh/g after 200 cycles at rates of 0.5 and 1C, respectively. These results highlight the synergistic coupling of lithiophilicity and conductivity in the Ag@SiO2@Ag coating, providing valuable insights into the field of lithiophilic chemistry and its potential for achieving high-performance batteries in the next generation.

3.
J Orthop Sci ; 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37407345

RESUMO

OBJECTIVE: This study aimed to analyze the stress and strain changes of the anterior cruciate ligament (ACL) at different knee flexion angles using a three-dimensional finite element model. METHODS: Computed tomography and magnetic resonance imaging scans were performed on the right knee of 30 healthy adult volunteers. The imaging data were used to construct a three-dimensional finite element model of the knee joint. The magnitude and concentration area of stress and strain of ACL at knee flexion angles 0°, 30°, 60° and 90° were assessed. RESULTS: The magnitude of stress remained consistent at 0-30° (P > 0.999) and decreased at 30-90° (P < 0.001, P = 0.005, respectively), while the magnitude of strain increased between 0° and 30° (P = 0.004) and decreased between 30° and 90° (P < 0.001, P = 0.004, respectively). The stress concentration area remained consistent at the proximal end, midsubstance, and distal end between 0° and 60° (P > 0.05). The concentration area of strain increased at the proximal end, decreased at the midsubstance between 0° and 30°, and remained consistent between 30° and 90° (P < 0.001). CONCLUSION: At the low knee flexion angle, ACL's magnitude of stress and strain reached the peak, and the concentration area of ACL strain gradually shifted from midsubstance to the proximal end.

4.
Front Cell Infect Microbiol ; 13: 1182480, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37293208

RESUMO

Background: Early and accurate diagnosis of infection-induced osteomyelitis, which often involves increased PD-L1 expression, is crucial for better treatment outcomes. Radiolabeled anti-PD-L1 nuclear imaging allows for sensitive and non-invasive whole-body assessments of PD-L1 expression. This study aimed to compare the efficacy of 18F-FDG and an 18F-labeled PD-L1-binding peptide probe (18F-PD-L1P) in PET imaging of implant-associated Staphylococcus aureus osteomyelitis (IAOM). Methods: In this study, we synthesized an anti-PD-L1 probe and compared its efficacy with 18F-FDG and 18F-PD-L1P in PET imaging of implant-associated Staphylococcus aureus osteomyelitis (IAOM). The %ID/g ratios (i.e., radioactivity ratios between the infected and non-infected sides) of both probes were evaluated for sensitivity and accuracy in post-infected 7-day tibias and post-infected 21 days, and the intensity of 18F-PD-L1P uptake was compared with pathological changes measured by PD-L1 immunohistochemistry (IHC). Results: Compared with 18F-FDG, 18F-PDL1P demonstrated higher %ID/g ratios for both post-infected 7-day tibias (P=0.001) and post-infected 21 days (P=0.028). The intensity of 18F-PD-L1P uptake reflected the pathological changes of osteomyelitic bones. In comparison to 18F-FDG, 18F-PDL1P provides earlier and more sensitive detection of osteomyelitis caused by S. aureus. Conclusion: Our findings suggest that the 18F-PDL1P probe is a promising tool for the early and accurate detection of osteomyelitis caused by S. aureus.


Assuntos
Osteomielite , Infecções Estafilocócicas , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Staphylococcus aureus , Tomografia por Emissão de Pósitrons/métodos , Osteomielite/diagnóstico por imagem , Infecções Estafilocócicas/diagnóstico por imagem , Infecções Estafilocócicas/metabolismo
5.
IEEE Trans Biomed Circuits Syst ; 17(5): 1022-1034, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37368798

RESUMO

Body channel communication (BCC) has become a promising candidate in wireless body area networks (WBAN) due to its advantages in energy efficiency and security. However, BCC transceivers face two challenges: diverse application requirements and varying channel conditions. To overcome these challenges, this article proposes a re-configurable architecture for BCC transceivers (TRXs), whose key parameters and communication protocols can be software-defined (SD) according to the requirements. In the proposed TRX, the programmable direct-sampling receiver (RX) is a combination of a programmable low-noise amplifier (LNA) and a fast-convergent successive approaching register analog-to-digital converter (SAR ADC), to achieve simple but energy-efficient data reception. The programmable digital transmitter (TX) is essentially implemented by a 2-bit DAC array to transmit either wide-band carrier-free signals like 4-level pulse amplitude modulation (PAM-4) or non-return-to-zero (NRZ) or narrow-band carrier-based signals like on-off keying (OOK) or frequency shift keying (FSK). The proposed BCC TRX is fabricated in a 180-nm CMOS process. Through an in-vivo experiment, it achieves up to 10-Mbps data rate and 119.2 pJ/bit energy efficiency. Moreover, the TRX is able to communicate under long-distance (1.5 m) and body-shielding conditions by switching its protocols, which shows the potential to be deployed in all categories of WBAN applications.


Assuntos
Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Desenho de Equipamento , Telemetria , Amplificadores Eletrônicos
6.
Nano Lett ; 23(13): 6216-6225, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37341290

RESUMO

It remains a challenge to artificially fabricate fibers with the macroscopic mechanical properties and characteristics of spider silk. Herein, a covalently cross-linked double-network strategy was proposed to disrupt the inverse relation of strength and toughness in the fabrication of ultratough and superstrong artificial polymer fibers. Our design utilized a strong fishnet-like structure based on immovable cellulose nanocrystal cross-links to mimic the function of the ß-sheet nanocrystallites and a slidable mechanically interlocked network based on polyrotaxane to imitate the dissipative stick-slip motion of the ß-strands in spider silk. The resultant fiber exhibited superior mechanical properties, including gigapascal tensile strength, a ductility of over 60%, and a toughness exceeding 420 MJ/m3. The fibers also showed robust biological functions similar to those of spider silks, demonstrating mechanical enhancement, energy absorption ability, and shape memory. A composite with our artificial fibers as reinforcing fibers exhibited remarkable tear and fatigue resistance.

7.
BMC Cardiovasc Disord ; 23(1): 189, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-37038117

RESUMO

The main manifestations of Takotsubo syndrome (TTS) are a spherical expansion of the left ventricle or near the apex and decreased systolic function. TTS is mostly thought to be induced by emotional stress, and the induction of TTS by severe infection is not often reported. A 72-year-old female patient with liver abscess reported herein was admitted due to repeated fever with a history of hypertension and impaired glucose tolerance. Her severe infection caused TTS, and her blood pressure dropped to 80/40 mmHg. IABP treatment was performed immediately and continued for 10 days, and comprehensive medication was administered. Based on her disease course and her smooth recovery, general insights and learnings may be: Adding to mental and other pathological stress reaction, serious infections from pathogenic microorganism could be of great important causation of stress reaction leading to TTS, while basic diseases such as coronary heart disease, hypertension, and diabetes were be of promoting factors; In addition to effective drug therapies for TTS, the importance of the timely using of IABP should be emphasized.


Assuntos
Hipertensão , Abscesso Hepático , Cardiomiopatia de Takotsubo , Humanos , Feminino , Idoso , Cardiomiopatia de Takotsubo/complicações , Cardiomiopatia de Takotsubo/diagnóstico por imagem , Cardiomiopatia de Takotsubo/tratamento farmacológico , Hipertensão/complicações , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Abscesso Hepático/complicações
8.
Materials (Basel) ; 15(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36556598

RESUMO

The ultra-wide bandgap semiconductor AlN has attracted a great deal of attention owing to its wide application potential in the field of electronics and optoelectronic devices. In this report, based on the mechanism of the physical vapor transport (PVT) growth of AlN crystal, the c- and m-plane AlN seed crystals were prepared simultaneously through special temperature field design. It is proved that AlN crystals with different orientations can be obtained at the same temperature field. The structure parameter of AlN crystal was obtained through the characteristic evaluations. In detail, XPS was used to analyze the chemical states and bonding states of the surface of seed crystals. The content of oxygen varied along with distinct orientations. Raman spectrum documented a small level of compressive stress on these crystal seeds. Tested results confirmed that the prepared AlN crystal seeds had high quality.

9.
World J Clin Cases ; 10(18): 6241-6246, 2022 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-35949855

RESUMO

BACKGROUND: At present, cases of esophageal neuroendocrine tumors combined with cardia adenocarcinoma are extremely rare worldwide, and there are no clinical reports. Herein, we describe such a case for clinical reference. CASE SUMMARY: The presence of cardia cancer and esophageal neuroendocrine tumors in a single patient has not yet been reported. The patient in this case underwent prompt endoscopic treatment and additional surgical resection. Pathology revealed the following: The distance between the cardia cancer and the esophageal neuroendocrine tumors was small, approximately 3 mm. Vascular invasion was observed. The esophageal neuroendocrine tumor was determined to be grade G3. According to the treatment guidelines, after the patient received an explanation of their condition, additional surgical procedures were provided in a timely manner. Early detection and early treatment can successfully prolong survival and improve the quality of life of patients. CONCLUSION: Early detection and early treatment can successfully prolong survival and improve the quality of life of such patients.

10.
Langmuir ; 38(28): 8657-8666, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35796103

RESUMO

Rational design of electrode materials with an excellent structure and morphology is crucial for improving electrochemical properties. Herein, various unique nanostructured Bi2S3 materials with controllable morphology were obtained through a simple and efficient oil bath reaction strategy. Bi2S3 with different morphologies can be obtained by regulating the polarity of solvent, and the lattice spacing can also be adjusted. The Bi2S3 nanomaterials obtained with ethanol as solvent (BS-3) show a three-dimensional nanoflower-like structure assembled with porous layers. The unique structure facilitates the transport of ions and accommodates the volume variation of Bi2S3 during energy storage. Consequently, BS-3 nanoflowers exhibited superior cycling stability and excellent high-rate capability for lithium storage (maintained a high capacity of 923.8 mA h g-1 after 950 cycles at 1.0 A g-1) and excellent sodium storage. We provide guidance for precise synthesis and energy storage application of Bi2S3 nanomaterials.

11.
J Orthop Surg Res ; 17(1): 285, 2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35597957

RESUMO

BACKGROUND: The aim of this study is to compare the clinical and biomechanical outcome of INFIX plus single with two sacroiliac screw fixation for unstable pelvic fractures of Type C. METHODS: Sixteen cadavers were randomly subjected to INFIX plus single or double sacroiliac screw fixations and then mounted onto the ElectroForce loading machine under different vertical loads. To investigate the clinical outcomes of the two techniques, nineteen patients were retrospectively analyzed. The main outcome measures were postoperative radiographic reduction grading (using the Tornetta and Matta grading system), functional outcome (using the Majeed scoring system), and incidence of complications. RESULTS: In the biomechanical study, INFIX plus double sacroiliac screw fixation showed better biomechanical stability than fixation with a single sacroiliac screw (p < 0.05). In our clinical case series, all 19 patients had bony union 6 months after the operation. INFIX plus double sacroiliac screw fixation also demonstrated a better functional outcome and a higher radiographic satisfactory rate than INFIX plus single sacroiliac screw fixation (79.25 ± 5.47; 91.33 ± 4.97; p < 0.05), (77.78% vs. 60%; p = 0.05). One patient in INFIX plus single-screw fixation group had screw loosening at 6-month follow-up postoperatively. One case in each group suffered heterotopic ossification and the lateral femoral cutaneous nerve paralysis, and one patient suffered from infection. CONCLUSION: INFIX plus double sacroiliac screw fixation demonstrated more stability in cadaveric biomechanical analysis and better clinical outcomes than INFIX plus single sacroiliac screw fixation.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Parafusos Ósseos , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Humanos , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/lesões , Ossos Pélvicos/cirurgia , Estudos Retrospectivos
12.
ACS Appl Mater Interfaces ; 14(13): 15324-15336, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35315652

RESUMO

Metal sulfides are promising anodes for potassium-ion batteries (PIBs) due to their high theoretical capacity and abundant active sites; however, their intrinsic low conductivity and poor cycling stability hampered their practical applications. Given this, the rational design of hybrid structures with high stability and fast charge transfer is a critical approach. Herein, CoS2/ZnS@rGO hybrid nanocomposites were demonstrated with stable cubic phases. The synergistic effect of the obtained bimetallic sulfide nanoparticles and highly conductive 2D rGO nanosheets facilitated excellent long-term cyclability for potassium ion storage. Such hybrid nanocomposites delivered remarkable ultrastable cycling performances in PIBs of 159, 106, and 80 mA h g-1 at 1, 1.5, and 2 A g-1 after 1800, 2100, and 3000 cycles, respectively. Moreover, the full-cell configuration with a perylene tetracarboxylic dianhydride organic cathode (CoS2/ZnS@rGO∥PTCDA) exhibited a better electrochemical performance. Besides, when the CoS2/ZnS@rGO nanocomposites were applied as an anode for sodium-ion batteries, the electrode demonstrated a reversible charge capacity of 259 mA h g-1 after 600 cycles at 2 A g-1. In situ X-ray diffraction and ex situ high-resolution transmission electron microscopy characterizations further confirmed the conversion reactions of CoS2/ZnS during insertion/desertion processes. Our synthesis strategy is also a general route to other bimetallic sulfide hybrid nanocomposites. This strategy opens up a new roadmap for exploring hybrid nanocomposites with feasible phase engineering for achieving excellent electrochemical performances in energy storage applications.

13.
J Colloid Interface Sci ; 616: 509-519, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35228047

RESUMO

The ternary transition metal oxides are promising anode material for lithium-ion batteries (LIBs). However, their practical applications are greatly hindered by the poor conductivity and huge volume changes. To solve the issues, urchin-like inverse spinel manganese (Mn) doped NiCo2O4 hierarchical microspheres were fabricated through a facile hydrothermal approach and subsequent annealing treatment. The as-obtained Mn-doped NiCo2O4 hold microsphere and sharp fiber-shaped needle multilevel nanoscale architecture, which effectively shortened Li ions (Li+) transmission path and improved the conductivity. In addition, the hierarchical urchin-like Mn-doped NiCo2O4 synthesized at annealing temperature (600 °C) manifested a larger capacity and better cycling performance by controlling the crystallinities and morphologies. As expected, it displays an outstanding cycling performance with a reversible capacity of about 945 mAh g-1 after 500 cycles at 2000 mA g-1. The kinetic analysis and galvanostatic intermittent titration technique (GITT) testing also verifies the superior pseudocapacitance contribution and fast elevated ion migration of Li+. Our work provides a promising design to develop suitable anode materials based on transition metal oxides for high-performance LIBs.

14.
Small ; 18(15): e2107252, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35224841

RESUMO

Suitable anode materials with high capacity and long cycling stability, especially capability at high current densities, are urgently needed to advance the development of potassium ion batteries (PIBs) and sodium ion batteries (SIBs). Herein, a porous Ni-doped FeSe2 /Fe3 Se4 heterojunction encapsulated in Se-doped carbon (NF11 S/C) is designed through selenization of MOFs precursor. The porous composite possesses enriched active sites and facilitates transport for both ion and electron. Ni-doping is adopted to enrich the lattice defects and active sites. The Se-C bond and carbon framework endow integrity of the composite and hamper aggregation of selenide nano-particles during potassiation/de-potassiation. The NF11 S/C exhibits exceptional rate performance and ultra-long cycling stability (177.3 mA h g-1 after 3050 cycles at 2 A g-1 for PIBs and 208.8 mA h g-1 after 2000 cycles at 8 A g-1 for SIBs). The potassiation/de-potassiation mechanism is investigated via ex-situ X-ray powder diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectrocopy and Raman analysis. PTCDA//NF11 S/C full cell stably cycles for 1200 cycles at 200 mA g-1 with a capacity of 103.7 mA h g-1 , indicating the high application potential of the electrode for highly stable rechargeable batteries.

15.
Nanomaterials (Basel) ; 11(10)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34684927

RESUMO

In the last 20 years, silicon quantum dots have received considerable attention from academic and industrial communities for research on readout, manipulation, storage, near-neighbor and long-range coupling of spin qubits. In this paper, we introduce how to realize a single spin qubit from Si-MOS quantum dots. First, we introduce the structure of a typical Si-MOS quantum dot and the experimental setup. Then, we show the basic properties of the quantum dot, including charge stability diagram, orbital state, valley state, lever arm, electron temperature, tunneling rate and spin lifetime. After that, we introduce the two most commonly used methods for spin-to-charge conversion, i.e., Elzerman readout and Pauli spin blockade readout. Finally, we discuss the details of how to find the resonance frequency of spin qubits and show the result of coherent manipulation, i.e., Rabi oscillation. The above processes constitute an operation guide for helping the followers enter the field of spin qubits in Si-MOS quantum dots.

16.
Biomed Pharmacother ; 141: 111909, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34328088

RESUMO

Ganoderma lucidum is a legendary traditional Chinese medicine with various bioactivities. This study was conducted (a) to explore the in vitro fermentation of the water extracts of G. lucidum fruiting body with Lactobacillus acidophilus and Bifidobacterium breve and (b) to investigate the effect of fermentation broth (GLFB) on dexamethasone (DEX)-induced immunosuppressed mice. Our results demonstrated that probiotic fermentation of G. lucidum fruiting body extracts underwent structural changing of major ganoderic acid components, such as ganoderic acid A (GA) into GC2, and this fermentation process involves changing of several metabolic pathways in the probiotic strains. GLFB could significantly improve the immunity, intestinal integrity, and gut microbiota dysbiosis in DEX-treated mice, and the immunostimulatory activity of GLFB was found closely related to its direct regulation on the expansion of CD4+ T cells in Peyer's patches of mice. These data implied that probiotic fermentation of G. lucidum fruiting body extracts promoted its immunostimulatory activity via biotransformation of components such as GA. This research provides a theoretical support for the development and application of G. lucidum fermentation by probiotics.


Assuntos
Adjuvantes Imunológicos/farmacologia , Dexametasona/farmacologia , Carpóforos/química , Imunossupressores/farmacologia , Probióticos/metabolismo , Reishi/metabolismo , Animais , Linfócitos T CD4-Positivos/metabolismo , Fermentação , Microbioma Gastrointestinal/efeitos dos fármacos , Ácidos Heptanoicos/farmacologia , Intestinos/efeitos dos fármacos , Lanosterol/análogos & derivados , Lanosterol/farmacologia , Contagem de Linfócitos , Masculino , Medicina Tradicional Chinesa , Camundongos , Camundongos Endogâmicos BALB C , Nódulos Linfáticos Agregados/citologia , Nódulos Linfáticos Agregados/efeitos dos fármacos , Reishi/química
17.
Sensors (Basel) ; 20(8)2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32295136

RESUMO

Today, as media and technology multitasking becomes pervasive, the majority of young people face a challenge regarding their attentional engagement (that is, how well their attention can be maintained). While various approaches to improve attentional engagement exist, it is difficult to produce an effect in younger people, due to the inadequate attraction of these approaches themselves. Here, we show that a single 30-min engagement with an attention restoration theory (ART)-inspired closed-loop software program (Virtual ART) delivered on a consumer-friendly virtual reality head-mounted display (VR-HMD) could lead to improvements in both general attention level and the depth of engagement in young university students. These improvements were associated with positive changes in both behavioral (response time and response time variability) and key electroencephalography (EEG)-based neural metrics (frontal midline theta inter-trial coherence and parietal event-related potential P3b). All the results were based on the comparison of the standard Virtual ART tasks (control group, n = 15) and closed-loop Virtual ART tasks (treatment group, n = 15). This study provides the first case of EEG evidence of a VR-HMD-based closed-loop ART intervention generating enhanced attentional engagement.


Assuntos
Atenção/fisiologia , Ansiedade/patologia , Eletroencefalografia , Feminino , Humanos , Masculino , Software , Realidade Virtual , Adulto Jovem
18.
Talanta ; 203: 1-8, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31202313

RESUMO

Lysosomes generally maintain the weak acidic microenvironment, to ensure highly efficient activity and functions of hydrolytic enzymes and proteins. Aberrations of the lysosomal pH may result in cellular functional changes and influence human physiology, possibly causing serious diseases. Small-molecular fluorescent probes based imaging techniques capable of providing information on target locations are considerably appreciated. Herein, by reducing the size of the typical lysosome targetable group 4-(2-aminoethyl) morpholine, we rationally designed a rhodamine analogue probe Ly-HN2AM with N-Aminomorpholine as the ring-closed switch and the lysosome targetable moiety for visualizing lysosomal pH changes. With the benefit of constructing multi-pentacyclic intramolecular hydrogen bond when binding with the H+, Ly-HN2AM gives a highly sensitive response towards pH values ranging from 4.79 to 6.07, with a remarkable higher pKa 5.35 over the typical 4-(2-aminoethyl) morpholine modified probes. The new probe was successfully applied to visualize pH value changes in lysosome-associated physiological and pathological processes with excellent photostability and low cytotoxicity, indicating the potential applications of lysosome specific bioimaging.


Assuntos
Corantes Fluorescentes/química , Lisossomos/metabolismo , Morfolinas/química , Rodaminas/química , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Humanos , Concentração de Íons de Hidrogênio , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Morfolinas/síntese química , Morfolinas/toxicidade , Rodaminas/síntese química , Rodaminas/toxicidade
19.
J Colloid Interface Sci ; 548: 233-243, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31004956

RESUMO

A novel and simple approach to preparing hierarchical zinc oxide/reduced graphene oxide (ZnO/RGO@RGO) composite is demonstrated using few-layered graphene oxide (GO) and metal zinc as starting materials following combined processes, including in-situ metal zinc reduction and catalyzed GO deoxygenation. Metal zinc can directly reduce GO sheets in aqueous GO suspension at room temperature to obtain a porous composite precursor (ZnO/RGO) with ZnO nanoparticles anchored on the RGO sheets. Then another RGO protecting layer is directly coated on the ZnO/RGO precursor to obtain the hierarchical ZnO/RGO@RGO composite. In this step, the exposed ZnO nanoparticles on the surface of ZnO/RGO play the role of catalyst to accelerate the deoxygenation of GO from the extra added GO aqueous suspension under mild hydrothermal condition. The reaction mechanism of metal zinc with GO aqueous suspension has been explored and the catalyst role of ZnO has been verified in this work. The prepared ZnO/RGO@RGO composite exhibited both stable cycling performance and good rate capability as anode for lithium-ion batteries. The method to prepare ZnO/RGO composite is economic and eco-friendly, and the ZnO catalyzing GO reduction opens a new approach to prepare graphene derivates.

20.
Talanta ; 192: 128-134, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30348367

RESUMO

Hypochlorous acid (HClO), one of the most important reactive oxygen species (ROS), is a potent antimicrobial agent for the immune system against invasive bacteria and a wide range of pathogens. Therefore, it is critical to develop sensitive and selective methods for visualization of HClO in biological samples. In this work, a two-photon fluorescent probe HN2-TP) with long-wavelength emission (far-red: 630 nm) based on rhodamine analogue for bioimaging HClO was developed. Owing to a specific HClO induced cyclization reaction, the new probe shows large fluorescence enhancement (about 106-fold), good linear range with high sensitivity (detection limit: 40 nM), high selectivity and fast response when monitoring HClO in vitro. More importantly, by successfully imaging HClO in living cells and tissues, this kind of two-photon fluorescent probe with long-wavelength emission is expected for accurate sensing in complex biosystems, which could eliminate undesired autofluorescence and self-absorption.


Assuntos
Corantes Fluorescentes/química , Ácido Hipocloroso/análise , Fígado/química , Fótons , Animais , Proliferação de Células , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Estrutura Molecular , Células RAW 264.7 , Ratos
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