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1.
Small ; 20(30): e2311975, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38396264

RESUMO

Transition metal oxides, fluorides, and sulfides are extensively studied as candidate electrode materials for lithium-ion batteries driven by the urgency of developing next-generation higher energy density lithium batteries. These conversion-type electrode materials often require nanosized active materials to enable a "smooth" lithiation and de-lithiation process during charge/discharge cycles, determined by their size, structure, and phase. Herein, the structural and chemical changes of Copper Disulfide (CuS2) hollow nanoparticles during the lithiation process through an in situ transmission electron microscopy (TEM) method are investigated. The study finds the hollow structure of CuS2 facilitates the quick formation of fluidic Li2S "drops," accompanied by a de-sulfurization to the Cu7S4 phase. Meanwhile, the metallic Cu phase emerges as fine nanoparticles and grows into nano-strips, which are embedded in the Li2S/Cu7S4 matrix. These complex nanostructured phases and their spatial distribution can lead to a low de-lithiation barrier, enabling fast reaction kinetics.

2.
J Phys Chem A ; 128(32): 6668-6676, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39106203

RESUMO

When the particle size of energetic materials is reduced to the nanoscale, significant changes occur in their properties and behavior. In this work, compression processes of three RDX nanoparticles (A, B, and C) were simulated using ReaxFF-lg. The mechanical, structural, and energetic responses of RDX nanoparticles during compression were revealed and characterized. Simulations reveal that the compression process of the nanoparticles can be divided into three stages: elastic stage, primary damage stage, and sustained damage stage. The temperature increase rate in the elastic phase is much lower than in the primary damage phase. In addition, we found that the smaller nanoparticle B presents a smaller elastic modulus and compressive strength, and it has a slower rate of temperature increase during the primary damage phase. Compared to cuboidal nanoparticles (A and B), the spherical nanoparticle C tends to absorb less energy during the elastic stage and exhibits slower damage rate during the primary damage stage. This is a key factor contributing to the low sensitivity of spherical nanoparticles.

3.
Chemistry ; 29(25): e202202716, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36806292

RESUMO

Plasmonic photocatalysis for CO2 reduction is attracting increasing attention due to appealing properties and great potential for real applications. In this review, the fundamentals of plasmonic photocatalysis and the most recent developments regarding its application in driving CO2 reduction are reported. Firstly, we present the review on the mechanism of plasmonic photocatalytic CO2 reduction, the energy transfer of plasmon, and the CO2 reduction process on the catalyst surface. Then, the modulation on the plasmonic nanostructures and also the semiconductor counterpart to regulate CO2 photoreduction is discussed. Next, the influence of the core-shell structure and the interface between the plasmonic metal and semiconductor on the CO2 photoreduction performance is also outlined. In addition, the latest progress on the emerging direction regarding the plasmonic photocatalysis for methane dry reforming with CO2 is especially emphasized. Finally, a summary on the challenges and prospects of this promising field are provided.

4.
Langmuir ; 39(49): 18031-18042, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38039553

RESUMO

Obviously, the dispersion of nanocatalytic materials has significant influence on their catalytic performance. In this study, an evaluation method for the dispersion of nanomaterials was established according to the different solid UV absorptions of different substances by taking the dispersion of nanocopper oxide (nano-CuO) in superfine ammonium perchlorate (AP) as an example. The nano-CuO/superfine AP composites with different nano-CuO dispersions can be obtained by changing the process parameters, such as varying the grinding method, the grinding strength, and the grinding time. Three replicate experiments were carried out for different composites to derive the average values of absorbance at 212 nm, and the dispersion of nano-CuO in superfine AP was calculated using the difference equation, as the solid UV curves at 210-214 nm were almost identical for each sample, especially at 212 nm. The properties of different samples were tested by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), differential scanning calorimetry (DSC), and thermogravimetry-mass spectrometry (TG-MS). The results show that the particle size and structure of superfine AP in the composites prepared by different methods were not changed. The XRD and IR techniques in this study were unable to characterize the dispersion of nano-CuO in the composites due to its low content. The dispersion of nano-CuO in the nano-CuO/superfine AP composites was significantly enhanced with the increase of grinding strength and grinding time, and the dispersion of nano-CuO was positively correlated with its catalytic performance, which means that the thermal decomposition performance of different composites improved with the increasing dispersion of nano-CuO. Highly dispersed nano-CuO exhibited a significant catalytic effect on superfine AP in TG-MS. The above conclusions demonstrate the accuracy of the difference equation for evaluating the dispersion of nanomaterials based on solid UV curves, which is expected to be used extensively in evaluating the dispersion of nanocatalytic materials in energetic materials.

5.
Molecules ; 28(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36615616

RESUMO

Energetic composite materials (ECMs) are the basic materials of polymer binder explosives and composite solid propellants, which are mainly composed of explosive crystals and binders. During the manufacturing, storage and use of ECMs, the bonding surface is prone to micro/fine cracks or defects caused by external stimuli such as temperature, humidity and impact, affecting the safety and service of ECMs. Therefore, substantial efforts have been devoted to designing suitable self-healing binders aimed at repairing cracks/defects. This review describes the research progress on self-healing binders for ECMs. The structural designs of these strategies to manipulate macro-molecular and/or supramolecular polymers are discussed in detail, and then the implementation of these strategies on ECMs is discussed. However, the reasonable configuration of robust microstructures and effective dynamic exchange are still challenges. Therefore, the prospects for the development of self-healing binders for ECMs are proposed. These critical insights are emphasized to guide the research on developing novel self-healing binders for ECMs in the future.

6.
Langmuir ; 38(49): 15234-15244, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36453942

RESUMO

As a new type of carbon material, graphene oxide aerogel (GA) is widely used in catalysis due to its porous structure, high-efficiency adsorption, and superb conductivity. In this study, GA was prepared into a dense coating layer surrounding ZnCo2O4/ZnO particles to form a composite GA-ZnCo2O4/ZnO by means of a hydrothermal, blast drying, and vacuum-freeze-drying approach applied to catalyze the thermal decomposition of ammonium perchlorate (AP). The physicochemical properties of the obtained GA-ZnCo2O4/ZnO were characterized by different analytical methods. Scanning electron microscopy (SEM) analysis exhibited that GA is coated on the surface of ZnCo2O4/ZnO, forming a dense layer. Brunner Emmet Teller (BET) measurement results show that GA-ZnCo2O4/ZnO has a smooth macropore distribution curve and a larger specific surface area. Moreover, The catalytic effect investigation on AP with GA-ZnCo2O4/ZnO: the high temperature decomposition (HTD) peak temperature of AP in the presence of 5 wt % GA-ZnCo2O4/ZnO was reduced from 441 to 294 °C, and the exotherm of AP was expanded from 205 to 1275 J/g at a heating rate of 15 °C/min. Through the calculation, GA-ZnCo2O4/ZnO makes the activation energy and Gibbs free energy of the AP pyrolysis lower so that the reaction is easier to occur. Thermogravimetric-mass (TG-MS) spectrometry revealed that during thermal decomposition of AP, GA-ZnCo2O4/ZnO leveraged the synergistic catalysis of ZnCo2O4/ZnO and GA that boosted the flow of electrons from ClO4- to O2 and increased the absorption of the gas product to accelerate the AP pyrolysis. These results provided a facile strategy to prepare GA-based composite catalysts with extraordinary application prospects in the domain of solid propellants.

7.
Angew Chem Int Ed Engl ; 60(35): 19222-19231, 2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-33991002

RESUMO

We reported an efficient multicomponent polyannulation for in situ generation of heteroaromatic hyperbranched polyelectrolytes by using readily accessible internal diynes and low-cost, commercially available arylnitriles, NaSbF6 , and H2 O/AcOH. The polymers were obtained in excellent yields (up to 99 %) with extraordinary high molecular weights (Mw up to 1.011×106 ) and low polydispersity indices. The resulting polymers showed good processibility and high quantum yields with tunable emission in the solid state, making them ideal materials for highly ordered fluorescent photopatterning. These hyperbranched polyelectrolytes also possessed strong ability to generate reactive oxygen species, which allowed their applications in efficient bacterial killing and customizable photodynamic patterning of living organisms in a simple and cost-effective way.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Hidrocarbonetos Aromáticos/farmacologia , Polieletrólitos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Bactérias/metabolismo , Compostos Heterocíclicos/química , Hidrocarbonetos Aromáticos/química , Estrutura Molecular , Peso Molecular , Polieletrólitos/síntese química , Polieletrólitos/química , Espécies Reativas de Oxigênio/metabolismo
8.
Malar J ; 19(1): 145, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32268906

RESUMO

BACKGROUND: Countries within the Greater Mekong Sub-region (GMS) of Southeast Asia have committed to eliminating malaria by 2030. Although the malaria situation has greatly improved, malaria transmission remains at international border regions. In some areas, Plasmodium vivax has become the predominant parasite. To gain a better understanding of transmission dynamics, knowledge on the changes of P. vivax populations after the scale-up of control interventions will guide more effective targeted control efforts. METHODS: This study investigated genetic diversity and population structures in 206 P. vivax clinical samples collected at two time points in two international border areas: the China-Myanmar border (CMB) (n = 50 in 2004 and n = 52 in 2016) and Thailand-Myanmar border (TMB) (n = 50 in 2012 and n = 54 in 2015). Parasites were genotyped using 10 microsatellite markers. RESULTS: Despite intensified control efforts, genetic diversity remained high (HE = 0.66-0.86) and was not significantly different among the four populations (P > 0.05). Specifically, HE slightly decreased from 0.76 in 2004 to 0.66 in 2016 at the CMB and increased from 0.80 in 2012 to 0.86 in 2015 at the TMB. The proportions of polyclonal infections varied significantly among the four populations (P < 0.05), and showed substantial decreases from 48.0% in 2004 to 23.7 at the CMB and from 40.0% in 2012 to 30.7% in 2015 at the TMB, with corresponding decreases in the multiplicity of infection. Consistent with the continuous decline of malaria incidence in the GMS over time, there were also increases in multilocus linkage disequilibrium, suggesting more fragmented and increasingly inbred parasite populations. There were considerable genetic differentiation and sub-division among the four tested populations. Temporal genetic differentiation was observed at each site (FST = 0.081 at the CMB and FST = 0.133 at the TMB). Various degrees of clustering were evident between the older parasite samples collected in 2004 at the CMB and the 2016 CMB and 2012 TMB populations, suggesting some of these parasites had shared ancestry. In contrast, the 2015 TMB population was genetically distinctive, which may reflect a process of population replacement. Whereas the effective population size (Ne) at the CMB showed a decrease from 4979 in 2004 to 3052 in 2016 with the infinite allele model, the Ne at the TMB experienced an increase from 6289 to 10,259. CONCLUSIONS: With enhanced control efforts on malaria, P. vivax at the TMB and CMB showed considerable spatial and temporal differentiation, but the presence of large P. vivax reservoirs still sustained genetic diversity and transmission. These findings provide new insights into P. vivax transmission dynamics and population structure in these border areas of the GMS. Coordinated and integrated control efforts on both sides of international borders are essential to reach the goal of regional malaria elimination.


Assuntos
Erradicação de Doenças , Variação Genética , Desequilíbrio de Ligação , Malária Vivax/prevenção & controle , Plasmodium vivax/fisiologia , China/epidemiologia , Genótipo , Humanos , Incidência , Malária Vivax/epidemiologia , Repetições de Microssatélites , Plasmodium vivax/genética , Dinâmica Populacional , Tailândia/epidemiologia
9.
J Am Chem Soc ; 141(28): 11259-11268, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31264856

RESUMO

Polyelectrolytes play an important role in both natural biological systems and human society, and their synthesis, functional exploration, and profound application are thus essential for biomimicry and creating new materials. In this study, we developed an efficient synthetic methodology for in situ generation of azonia-containing polyelectrolytes in a one-pot manner by using readily accessible nonionic reactant in the presence of commercially available cheap ionic species. The resulting polyelectrolytes are emissive in the solid state and can readily form luminescent photopatterns with different colors. The azonia-containing polyelectrolytes possess extraordinary potency of reactive oxygen species (ROS) generation, enabling them to impressively kill methicillin-resistant Staphylococcus aureus (MRSA), a drug resistant superbug, both in vitro and in vivo.


Assuntos
Amidas/farmacologia , Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Polieletrólitos/farmacologia , Amidas/química , Antibacterianos/síntese química , Antibacterianos/química , Luminescência , Staphylococcus aureus Resistente à Meticilina/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Processos Fotoquímicos , Polieletrólitos/síntese química , Polieletrólitos/química , Espécies Reativas de Oxigênio/metabolismo
10.
Nanotechnology ; 31(8): 085708, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675746

RESUMO

3D flower-like Fe3S4 microspheres and quasi-sphere Fe3S4-RGO hybrid-architectures were successfully fabricated by a facile template-free hydrothermal method. The results of morphology revealed that the single Fe3S4 was composed of many nanoflakes and the Fe3S4-RGO composites mainly distributed together into a ball up and down the RGO sheet. The electromagnetic parameters of the single Fe3S4 and Fe3S4-RGO composites could be controlled by adjusting different filler loading and the addition of different GO to achieve impedance matching. Both the single Fe3S4 and Fe3S4-RGO composites exhibited an excellent EM absorption ability. The minimum reflection loss (RL) of the single Fe3S4 with 50% filler loading could achieve -66.87 dB at 10.57 GHz for the thickness of 2.2 mm, and the absorption bandwidth (RL < -10 dB) could reach 3.49 GHz. For the Fe3S4-RGO composites, the minimum RL of FSR-1 could be -40.25 dB at 9.67 GHz with the thickness of 2.0 mm. In addition, the effective absorption bandwidth of FSR-2 could reach 3.85 GHz at only 1.45 mm and the minimum RL was -29.25 dB at 14.24 GHz. Consequently, the single Fe3S4 and Fe3S4-RGO composites are promising materials as a high performance and adjustable EM wave absorber.

11.
J Am Chem Soc ; 138(33): 10630-5, 2016 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-27488536

RESUMO

A series of ladder-type fused heteroacenes consisting of thiophenes and benzothiophenes were synthesized and functionalized with thiol groups for single-molecule electrical measurements via a scanning tunneling microscopy break-junction method. It was found that this molecular wire system possesses exceptional charge transport properties with weak length dependence. The tunneling decay constant ß was estimated to be 0.088 and 0.047 Å(-1) under 0.1 and 0.5 bias, respectively, which is one of the lowest ß values among other non-metal-containing molecular wires, indicating that a planar ladder structure favors charge transport. Transition voltage spectroscopy showed that the energy barrier decreases as the length of the molecule increases. The general trend of the energy offsets derived from the transition voltage via the Newns-Anderson model agrees well with that of the Fermi/HOMO energy level difference. Nonequilibrium Green's function/density functional theory was used to further investigate the transport process in these molecular wires.

12.
Biosens Bioelectron ; 256: 116242, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38631133

RESUMO

Psychiatric disorders are associated with serve disturbances in cognition, emotional control, and/or behavior regulation, yet few routine clinical tools are available for the real-time evaluation and early-stage diagnosis of mental health. Abnormal levels of relevant biomarkers may imply biological, neurological, and developmental dysfunctions of psychiatric patients. Exploring biosensors that can provide rapid, in-situ, and real-time monitoring of psychiatric biomarkers is therefore vital for prevention, diagnosis, treatment, and prognosis of mental disorders. Recently, psychiatric biosensors with high sensitivity, selectivity, and reproducibility have been widely developed, which are mainly based on electrochemical and optical sensing technologies. This review presented psychiatric disorders with high morbidity, disability, and mortality, followed by describing pathophysiology in a biomarker-implying manner. The latest biosensors developed for the detection of representative psychiatric biomarkers (e.g., cortisol, dopamine, and serotonin) were comprehensively summarized and compared in their sensitivities, sensing technologies, applicable biological platforms, and integrative readouts. These well-developed biosensors are promising for facilitating the clinical utility and commercialization of point-of-care diagnostics. It is anticipated that mental healthcare could be gradually improved in multiple perspectives, ranging from innovations in psychiatric biosensors in terms of biometric elements, transducing principles, and flexible readouts, to the construction of 'Big-Data' networks utilized for sharing intractable psychiatric indicators and cases.


Assuntos
Biomarcadores , Técnicas Biossensoriais , Transtornos Mentais , Humanos , Biomarcadores/análise , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Dopamina/análise , Técnicas Eletroquímicas/métodos , Transtornos Mentais/diagnóstico , Transtornos Mentais/fisiopatologia , Saúde Mental , Serotonina/análise , Serotonina/sangue , Serotonina/metabolismo
13.
Biosens Bioelectron ; 250: 116045, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38301546

RESUMO

Skin cancer is a critical global public health concern, with melanoma being the deadliest variant, correlated to 80% of skin cancer-related deaths and a remarkable propensity to metastasize. Despite notable progress in skin cancer prevention and diagnosis, the limitations of existing methods accentuate the demand for precise diagnostic tools. Biosensors have emerged as valuable clinical tools, enabling rapid and reliable point-of-care (POC) testing of skin cancer. This review offers insights into skin cancer development, highlights essential cutaneous melanoma biomarkers, and assesses the current landscape of biosensing technologies for diagnosis. The comprehensive analysis in this review underscores the transformative potential of biosensors in revolutionizing melanoma skin cancer diagnosis, emphasizing their critical role in advancing patient outcomes and healthcare efficiency. The increasing availability of these approaches supports direct diagnosis and aims to reduce the reliance on biopsies, enhancing POC diagnosis. Recent advancements in biosensors for skin cancer diagnosis hold great promise, with their integration into healthcare expected to enhance early detection accuracy and reliability, thereby mitigating socioeconomic disparities.


Assuntos
Técnicas Biossensoriais , Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Técnicas Biossensoriais/métodos , Reprodutibilidade dos Testes , Pele
14.
Adv Sci (Weinh) ; 11(12): e2306560, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38225744

RESUMO

Point-of-care (POC) has the capacity to support low-cost, accurate and real-time actionable diagnostic data. Microneedle sensors have received considerable attention as an emerging technique to evolve blood-based diagnostics owing to their direct and painless access to a rich source of biomarkers from interstitial fluid. This review systematically summarizes the recent innovations in microneedle sensors with a particular focus on their utility in POC diagnostics and personalized medicine. The integration of various sensing techniques, mostly electrochemical and optical sensing, has been established in diverse architectures of "lab-on-a-microneedle" platforms. Microneedle sensors with tailored geometries, mechanical flexibility, and biocompatibility are constructed with a variety of materials and fabrication methods. Microneedles categorized into four types: metals, inorganics, polymers, and hydrogels, have been elaborated with state-of-the-art bioengineering strategies for minimally invasive, continuous, and multiplexed sensing. Microneedle sensors have been employed to detect a wide range of biomarkers from electrolytes, metabolites, polysaccharides, nucleic acids, proteins to drugs. Insightful perspectives are outlined from biofluid, microneedles, biosensors, POC devices, and theragnostic instruments, which depict a bright future of the upcoming personalized and intelligent health management.


Assuntos
Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Testes Imediatos , Proteínas , Agulhas , Biomarcadores
15.
Adv Sci (Weinh) ; 11(30): e2309509, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38884139

RESUMO

Dermal tattoo biosensors are promising platforms for real-time monitoring of biomarkers, with skin used as a diagnostic interface. Traditional tattoo sensors have utilized small molecules as biosensing elements. However, the rise of synthetic biology has enabled the potential employment of engineered bacteria as living analytical tools. Exploiting engineered bacterial sensors will allow for potentially more sensitive detection across a broad biomarker range, with advanced processing and sense/response functionalities using genetic circuits. Here, the interfacing of bacterial biosensors as living analytics in tattoos is shown. Engineered bacteria are encapsulated into micron-scale hydrogel beads prepared through scalable microfluidics. These biosensors can sense both biochemical cues (model biomarkers) and biophysical cues (temperature changes, using RNA thermometers), with fluorescent readouts. By tattooing beads into skin models and confirming sensor activity post-tattooing, our study establishes a foundation for integrating bacteria as living biosensing entities in tattoos.


Assuntos
Técnicas Biossensoriais , Tatuagem , Técnicas Biossensoriais/métodos , Tatuagem/métodos , Humanos , Pele/microbiologia , Pele/metabolismo , Biomarcadores/metabolismo , Biomarcadores/análise , Bactérias/genética , Bactérias/metabolismo
16.
Biosens Bioelectron ; 262: 116542, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38991372

RESUMO

Continuous glucose monitors are crucial for diabetes management, but invasive sampling, signal drift and frequent calibrations restrict their widespread usage. Microneedle sensors are emerging as a minimally-invasive platform for real-time monitoring of clinical parameters in interstitial fluid. Herein, a painless and flexible microneedle sensing patch is constructed by a mechanically-strong microneedle base and a thin layer of fluorescent hydrogel sensor for on-site, accurate, and continuous glucose monitoring. The Förster resonance energy transfer (FRET)-based hydrogel sensors are fabricated by facile photopolymerizations of acryloylated FRET pairs and glucose-specific phenylboronic acid. The optimized hydrogel sensor enables quantification of glucose with reversibility, high selectivity, and signal stability against photobleaching. Poly (ethylene glycol diacrylate)-co-polyacrylamide hydrogel is utilized as the microneedle base, facilitating effective skin piercing and biofluid extraction. The integrated microneedle sensor patch displays a sensitivity of 0.029 mM-1 in the (patho)physiological range, a low detection limit of 0.193 mM, and a response time of 7.7 min in human serum. Hypoglycemia, euglycemia and hyperglycemia are continuously monitored over 6 h simulated meal and rest activities in a porcine skin model. This microneedle sensor with high transdermal analytical performance offers a powerful tool for continuous diabetes monitoring at point-of-care settings.


Assuntos
Técnicas Biossensoriais , Automonitorização da Glicemia , Glicemia , Transferência Ressonante de Energia de Fluorescência , Hidrogéis , Agulhas , Dispositivos Eletrônicos Vestíveis , Humanos , Técnicas Biossensoriais/instrumentação , Hidrogéis/química , Automonitorização da Glicemia/instrumentação , Glicemia/análise , Animais , Suínos , Polietilenoglicóis/química , Limite de Detecção , Resinas Acrílicas/química , Desenho de Equipamento , Monitoramento Contínuo da Glicose , Ácidos Borônicos
17.
ACS Appl Mater Interfaces ; 16(40): 53793-53800, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39340419

RESUMO

The lithium lanthanum titanium oxide (LLTO) perovskite is one type of superior lithium (Li)-ion conductor that is of great interest as a solid-state electrolyte for all-solid-state lithium batteries. Structural defects and impurity phases formed during the synthesis of LLTO largely affect its Li-ion conductivity, yet the underlying Li+ diffusion mechanism at the atomic scale is still under scrutiny. Herein, we use aberration-corrected transmission electron microscopy to perform a thorough structural characterization of the LLTO ceramic pellet. We reveal a prevalent transient phase transition of (La, Ti)2O3 existing at the antiphase boundaries between single-crystalline LLTO domains. This transient phase exhibits a specific crystal orientation with the LLTO phase and shows a gradual structural transition to a tetragonal LLTO structure, which enables detailed crystallographic analysis to correlate their formation to the sintering process of LLTO powders into ceramic pellets. We also find that Li diffusion is retarded by this phase and correlated with the excess amount of La, which is corroborated by the theoretical evaluation of the atomistic mechanisms of Li diffusion across this phase.

18.
Lab Chip ; 24(9): 2454-2467, 2024 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-38644805

RESUMO

Safe, accurate, and reliable analysis of urinary biomarkers is clinically important for early detection and monitoring of the progression of chronic kidney disease (CKD), as it has become one of the world's most prevalent non-communicable diseases. However, current technologies for measuring urinary biomarkers are either time-consuming and limited to well-equipped hospitals or lack the necessary sensitivity for quantitative analysis and post a health risk to frontline practitioners. Here we report a robust paper-based dual functional biosensor, which is integrated with the clinical urine sampling vial, for the simultaneous and quantitative analysis of pH and glucose in urine. The pH sensor was fabricated by electrochemically depositing IrOx onto a paper substrate using optimised parameters, which enabled an ultrahigh sensitivity of 71.58 mV pH-1. Glucose oxidase (GOx) was used in combination with an electrochemically deposited Prussian blue layer for the detection of glucose, and its performance was enhanced by gold nanoparticles (AuNPs), chitosan, and graphite composites, achieving a sensitivity of 1.5 µA mM-1. This dual function biosensor was validated using clinical urine samples, where a correlation coefficient of 0.96 for pH and 0.98 for glucose detection was achieved with commercial methods as references. More importantly, the urine sampling vial was kept sealed throughout the sample-to-result process, which minimised the health risk to frontline practitioners and simplified the diagnostic procedures. This diagnostic platform, therefore, holds high promise as a rapid, accurate, safe, and user-friendly point-of-care (POC) technology for the analysis of urinary biomarkers in frontline clinical settings.


Assuntos
Técnicas Biossensoriais , Papel , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Concentração de Íons de Hidrogênio , Ouro/química , Glucose/análise , Urinálise/instrumentação , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Técnicas Eletroquímicas , Nanopartículas Metálicas/química , Grafite/química , Biomarcadores/urina
19.
Biosens Bioelectron ; 249: 116003, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38227993

RESUMO

Contact lens sensors have been emerging as point-of-care devices in recent healthcare developments for ocular physiological condition monitoring and diagnosis. Fluorescence sensing technologies have been widely applied in contact lens sensors due to their accuracy, high sensitivity, and specificity. As ascorbic acid (AA) level in tears is closely related to ocular inflammation, a fluorescent contact lens sensor incorporating a BSA-Au nanocluster (NC) probe is developed for in situ tear AA detection. The NCs are firstly synthesized to obtain a fluorescent probe, which exhibits high reusability through the quench/recover (KMnO4/AA) process. The probe is then encapsulated with 15 wt% of poly(vinyl alcohol) (PVA) and 1.5 wt% of citric acid (CA) film, and implemented on a closed microfluidic contact lens sensing region. The laser-ablated microfluidic channel in contact lens sensors allows for tear fluid to flow through the sensing region, enabling an in-situ detection of AA. Meanwhile, a smartphone application accompanied by a customized 3D printed readout box is developed for image caption and algorism to quantitative analysis of AA levels. The contact lens sensor is tested within the readout box and the emission signal is collected through the smartphone camera at room temperature with an achieved LOD of 0.178 mmol L-1 (0.0-1.2 mmol L-1). The operational and storage lifetime is also evaluated to characterize the sensor properties and resulted in 20 h and 10 days, respectively. The reusable AA contact lens sensor is promising to lead to an alternative accessible diagnostic method for ocular inflammation in point-of-care settings.


Assuntos
Técnicas Biossensoriais , Lentes de Contato , Humanos , Monitorização Fisiológica , Smartphone , Inflamação/diagnóstico , Lágrimas
20.
Ultrason Sonochem ; 104: 106827, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38412678

RESUMO

It is of great significance to prepare liners with excellent inhibition of energetic plasticizer migration and gas barrier properties. Here, we have successfully prepared magnetic iron oxide decorated reduced-graphene-oxide nanosheets (MRGO) by using ultrasound-assisted method. The obtained MRGO nanosheet-fillers were filled into hydroxyl-terminated polybutadiene (HTPB) which was exposed to a magnetic field (200 mT) to achieve ordered orientation of MRGO in the HTPB matrix (Ordered MRGO/HTPB). The laser confocal microscopy demonstrates that MRGO exhibit ordered orientation structure in HTPB matrix with good dispersion, which renders the HTPB composite liners exhibiting high gas and plasticizer barrier capability, with a reduction of 18.9 % in water vapor permeability and a decrease of 14.1 % in dibutyl phthalate (DBP) migration equilibrium concentration as compared with those of random MRGO embedded HTPB composite liners (Random MRGO/HTPB). Moreover, a theoretical model accounting for such enhanced gas/plasticizer barrier performance of HTPB due to the implantation of order aligned MRGO was established, which shows that the effective diffusion pathways of plasticizer/gas for liner penetration would be significantly enhanced when the MRGO nanosheets are oriented within the HTPB matrix. This work provides an effective and facile strategy toward the design and development of composite liners with high plasticizer/gas barrier performance for industrial applications.

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