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2.
Nature ; 630(8017): 631-635, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38811739

RESUMO

The increasing demands for more efficient and brighter thin-film light-emitting diodes (LEDs) in flat-panel display and solid-state lighting applications have promoted research into three-dimensional (3D) perovskites. These materials exhibit high charge mobilities and low quantum efficiency droop1-6, making them promising candidates for achieving efficient LEDs with enhanced brightness. To improve the efficiency of LEDs, it is crucial to minimize nonradiative recombination while promoting radiative recombination. Various passivation strategies have been used to reduce defect densities in 3D perovskite films, approaching levels close to those of single crystals3. However, the slow radiative (bimolecular) recombination has limited the photoluminescence quantum efficiencies (PLQEs) of 3D perovskites to less than 80% (refs. 1,3), resulting in external quantum efficiencies (EQEs) of LED devices of less than 25%. Here we present a dual-additive crystallization method that enables the formation of highly efficient 3D perovskites, achieving an exceptional PLQE of 96%. This approach promotes the formation of tetragonal FAPbI3 perovskite, known for its high exciton binding energy, which effectively accelerates the radiative recombination. As a result, we achieve perovskite LEDs with a record peak EQE of 32.0%, with the efficiency remaining greater than 30.0% even at a high current density of 100 mA cm-2. These findings provide valuable insights for advancing the development of high-efficiency and high-brightness perovskite LEDs.

3.
Se Pu ; 42(3): 296-303, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38503707

RESUMO

Aromatic amines are a class of compounds bearing amino groups on their benzene rings; these compounds are important raw materials for the industrial production of rubber chemicals, pesticides, dyes, pharmaceuticals, photosensitive chemicals, and agricultural chemicals. Research has revealed that some aromatic amines teratogenetic, carcinogenic, and mutagenic properties. Given the high toxicity and potential harm caused by aromatic amines, monitoring their levels in water sources is critical. Aromatic amines are among the 14 strategic environmental pollutants blacklisted in China, and assessing their exposure levels is essential for protecting human health and the environment. At present, the standard method for detecting aromatic amines in water is liquid-liquid extraction-gas chromatography-mass spectrometry (LLE-GC-MS). However, this method has the disadvantages of large sample size requirement, complex operation, long analysis time, and high reagent consumption. In this study, instead of traditional LLE technology, cloud point extraction (CPE) technology was used in combination with GC-MS to establish an efficient, sensitive, and environment-friendly method for the detection of nine aromatic amines, namely, 2-chloramine, 3-chloramine, 4-chloramine, 2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 1-naphthylamine, 2-naphthylamine, and 4-aminobenzene, in water. Triton X-114 was used as the extraction agent. The main experimental parameters were optimized using a single-factor optimization method. The aromatic amines in various water samples were quantitatively analyzed using GC-MS. The nine aromatic amines were separated on a DB-35 MS capillary column (30 m×0.25 mm×0.25 µm). The mass spectrometer was operated in selected ion monitoring (SIM) mode, and quantitative analysis was performed using the internal standard method. The results demonstrated that all nine aromatic amines could be completely separated within 16 min and had good linearities within accurate mass concentration ranges, with correlation coefficients (R2) greater than 0.998. The limits of detection (LODs) and quantification (LOQs) of these aromatic amines in water were 0.12-0.48 and 0.40-1.60 µg/L, respectively. The accuracy and precision of the method were assessed via the determination of aromatic amines in surface water of drinking water sources, offshore seawater, wastewater of the typical printing and dyeing industry at levels of 2.0 and 10.0 µg/L. The recoveries of the aromatic amines in surface water of drinking water sources were 81.1%-109.8%, with intra-day and inter-day relative standard deviations (RSDs) of 0.7%-5.2% (n=6) and 1.6%-6.2% (n=3), respectively. The recoveries of the aromatic amines in offshore seawater were 83.0%-115.8%, with intra-day RSDs (n=6) of 1.5%-8.6% and inter-day RSDs (n=3) of 2.4%-12.2%. The recoveries of the nine aromatic amines in wastewater of the typical printing and dyeing industry were 91.0%-120.0%, with intra-day RSDs (n=6) of 2.9%-12.9% and inter-day RSDs (n=3) of 2.5%-13.1%. The established method was used to detect nine aromatic amines in actual water samples. No aromatic amines were detected in the surface water of drinking water sources or offshore seawater samples. However, 2-chloramine, 4-chloramine, and 4-aminobenzene, which are frequently used in the printing and dyeing industry, were detected in the wastewater of the typical printing and dyeing industry samples. The proposed method offers the advantages of simple operation, high sensitivity, low cost, low organic reagent requirement, and good repeatability. Thus, this method provides reliable technical support for studying the residual status and environmental behavior of aromatic amines in water.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38485684

RESUMO

OBJECTIVE: Cancer poses a great threat to human health, and effective drugs to treat it are always needed. Several compounds containing a 2-aminopyrazine framework have been identified as antitumor agents with SHP2 inhibition activities. This current work aimed to search for more potent novel compounds possessing a 2-aminopyrazine moiety with antitumor activities. METHODS: A series of 12 novel 2-aminopyrazine derivatives was synthesized, and their structures were confirmed by spectroscopic techniques. The inhibitory activities of all the synthesized compounds against MDA-MB-231 and H1975 cancer cell lines were evaluated by an MTT assay. The most potent compound 3e was analyzed by flow cytometry. Subsequently, computational studies were performed to investigate the possible antitumor mechanisms of compound 3e. RESULTS: The results indicated that compound 3e exhibited potent antitumor activities with IC50 values of 11.84±0.83µM against H1975 cells and 5.66±2.39µM against MDA-MB-231 cells, which were more potent than the SHP2 inhibitor GS493 (IC50 = 19.08±1.01 µM against H1975 cells and IC50 = 25.02±1.47 µM against MDA-MB-231 cells). Further analysis by flow cytometry demonstrated that compound 3e induced cell apoptosis in H1975 cells. The results of the molecular docking and MD simulations, including RMSD, RMSF, PCA, DCCM and binding energy and decomposition analyses, revealed that compound 3e probably selectively inhibited SHP2. CONCLUSION: A new compound having a 2-aminopyrazine substructure with potent inhibitory activities against the H1975 and MDA-MB-231 cancer cells was obtained, meriting further investigation as an antitumor drug.

5.
Nat Nanotechnol ; 19(5): 632-637, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38216685

RESUMO

Environmentally friendly tin (Sn) perovskites have received considerable attention due to their great potential for replacing their toxic lead counterparts in applications of photovoltaics and light-emitting diodes (LEDs). However, the device performance of Sn perovskites lags far behind that of lead perovskites, and the highest reported external quantum efficiencies of near-infrared Sn perovskite LEDs are below 10%. The poor performance stems mainly from the numerous defects within Sn perovskite crystallites and grain boundaries, leading to serious non-radiative recombination. Various epitaxy methods have been introduced to obtain high-quality perovskites, although their sophisticated processes limit the scalable fabrication of functional devices. Here we demonstrate that epitaxial heterodimensional Sn perovskite films can be fabricated using a spin-coating process, and efficient LEDs with an external quantum efficiency of 11.6% can be achieved based on these films. The film is composed of a two-dimensional perovskite layer and a three-dimensional perovskite layer, which is highly ordered and has a well-defined interface with minimal interfacial areas between the different dimensional perovskites. This unique nanostructure is formed through direct spin coating of the perovskite precursor solution with tryptophan and SnF2 additives onto indium tin oxide glass. We believe that our approach will provide new opportunities for further developing high-performance optoelectronic devices based on heterodimensional perovskites.

6.
Sci Total Environ ; 903: 165925, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37544439

RESUMO

Landfill leachate is an essential source of pathogens and antibiotic resistance genes (ARGs) in the environment. However, information on the removal behavior of pathogens and ARGs during the leachate treatment and the impact on surrounding groundwater is limited. In this study, we investigated the effects of leachate treatment on the removal of pathogens and ARGs with metagenomic sequencing, as well as the impact of landfill effluent on groundwater. It is shown that the leachate treatment could not completely remove pathogens and ARGs. Twenty-nine additional pathogens and twenty-nine ARGs were newly identified in the landfill effluent. The relative abundance of pathogens and multiple antibiotic resistance genes decreased after ultrafiltration but relative abundance increased after reverse osmosis. In addition, the relative abundances of Acinetobacter baumannii, Erwinia amylovora, Escherichia coli, Fusarium graminearum, Klebsiella pneumoniae, and Magnaporthe oryzae, as well as mdtH, VanZ, and blaOXA-53 increased significantly in the landfill effluent compared to the untreated leachate. The relative abundance of some mobile genetic elements (tniA, tniB, tnpA, istA, IS91) in leachate also increased after ultrafiltration and reverse osmosis. The size of pathogens, the size and properties of ARGs and mobile genetic elements, and the materials of ultrafiltration and reverse osmosis membranes may affect the removal effect of pathogens, ARGs and mobile genetic elements in leachate treatment process. Interestingly, the pathogens and ARGs in landfill effluent were transferred to groundwater according to SourceTracker. The ARGs, mobile genetic elements, and pathogens that are difficult to remove in the leachate treatment process, provide a reference for optimizing the leachate treatment process and improving the control of pathogens and ARGs. Furthermore, this study clarifies the effect of landfill leachate sources of pathogens and ARGs in groundwater.

7.
Acta Biomater ; 170: 185-201, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37634835

RESUMO

The incidence of screw loosening, migration, and pullout caused by the insufficient screw-bone fixation stability is relatively high in clinical practice. To solve this issue, the auxetic unit-based porous bone screw (AS) has been put forward in our previous work. Its favorable auxetic effect can improve the primary screw-bone fixation stability after implantation. However, porous structure affected the fatigue behavior and in vivo longevity of bone screw. In this study, in vitro fatigue behaviors and in vivo osseointegration performance of the re-entrant unit-based titanium auxetic bone screw were studied. The tensile-tensile fatigue behaviors of AS and nonauxetic bone screw (NS) with the same porosity (51%) were compared via fatigue experiments, fracture analysis, and numerical simulation. The in vivo osseointegration of AS and NS were compared via animal experiment and biomechanical analysis. Additionally, the effects of in vivo dynamic tensile loading on the osseointegration of AS and NS were investigated and analyzed. The fatigue strength of AS was approximately 43% lower while its osseointegration performance was better than NS. Under in vivo dynamic tensile loading, the osseointegration of AS and NS both improved significantly, with the maximum increase of approximately 15%. Preferrable osseointegration of AS might compensate for the shortage of fatigue resistance, ensuring its long-term stability in vivo. Adequate auxetic effect and long-term stability of the AS was supposed to provide enough screw-bone fixation stability to overcome the shortages of the solid bone screw, developing the success of surgery and showing significant clinical application prospects in orthopedic surgery. STATEMENT OF SIGNIFICANCE: This research investigated the high-cycle fatigue behavior of re-entrant unit-based auxetic bone screw under tensile-tensile cyclic loading and its osseointegration performance, which has not been focused on in existing studies. The fatigue strength of auxetic bone screw was lower while the osseointegration was better than non-auxetic bone screw, especially under in vivo tensile loading. Favorable osseointegration of auxetic bone screw might compensate for the shortage of fatigue resistance, ensuring its long-term stability and longevity in vivo. This suggested that with adequate auxetic effect and long-term stability, the auxetic bone screw had significant application prospects in orthopedic surgery. Findings of this study will provide a theoretical guidance for design optimization and clinical application of the auxetic bone screw.

8.
Adv Sci (Weinh) ; 10(27): e2303238, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37518855

RESUMO

Walnut shell is lightweight material with high-strength and toughening characteristics, but it is different from other nut shells' microstructure with two or three short sclerotic cell layers and long bundle fibers. It is essential to explore the fracture resistance biomechanism of lightweight walnut shell and how to prevent damage of bionic structure. In this study, it is found that the asymmetric mass center and geometric center dissipated impact energy to the whole shell without loading concentration in the loading area. Diaphragma juglandis is a special structure improved walnut shell's toughening. The S-shape gradient porosity/elastic modulus distribution combined with pits on single auxetic sclerotic cells requires higher energy to crack expansion, then decreases its fracture behavior. These fantastic findings inspire to design fracture resistance devices including helmets, armor, automobile anti-collision beams, and re-entry capsule in spacecraft.

9.
Front Cell Infect Microbiol ; 13: 1124256, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36814445

RESUMO

Background and Aims: Ulcerative colitis (UC) has become a global public health concern, and is in urgent need of novel therapies. Fecal microbiota transplantation (FMT) targeting gut microbiota has recently been applied to the treatment of UC. Despite its recent successes, it is still largely unknown how FMT functionally modulates the gut microbiota and improves the disease. Methods: We prospectively collected fecal samples from the 40 mice (30 mice for dextran sulfate sodium (DSS)-induced, 10 for controls), followed by Propidium monoazide treatment for 16S rRNA gene sequencing. These 30 mice were divided equally into 3 groups, which were transplanted with original donor microbiota (DO), inactivated donor microbiota (DI) and saline, respectively. Subsequently, we used 16S rRNA gene sequencing to analyze the viable gut bacteria of ulcerative colitis (UC) mice and histological analysis to evaluate the effects of fecal microbiota transplantation (FMT) with viable microbiota. Results: We demonstrated that the community structure of viable bacteria was significantly different from fecal bacteria based on total DNA. Furthermore, the intestinal viable microbiota and colonic mucosal structure of mice were significantly changed by DSS induction. The histological analysis showed that only the mice treated with original donor microbiota group (HF) achieved a significant improvement. Compared with inactivated donor microbiota group (IF) and saline (NF), Lactobacillus and Halomonas were significantly enriched in the HF group. Conclusion: We inferred that only live bacteria from human donor reversed the histopathology and symptoms of UC in mice and altered the gut microbiota. The activity of gut microbiota in donor samples should be considered in FMT and that detailed analysis of viable microbiota is essential to understand the mechanisms by which FMT produces therapeutic effects in the future.


Assuntos
Colite Ulcerativa , Colite , Camundongos , Humanos , Animais , Transplante de Microbiota Fecal , RNA Ribossômico 16S , Fezes/microbiologia , Bactérias , Sulfato de Dextrana , Colite/terapia
10.
Comput Methods Biomech Biomed Engin ; 26(12): 1510-1521, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36129013

RESUMO

The helmet plays an important role in protection of pilot's head and enhances the pilot's capabilities and performance significantly with the use of mounted devices such as the Night Vision Goggle (NVG). However, the use of helmet-mounted devices might increase the risk of injury due to the increased helmet weight and change in the centre of gravity of head. In this study, four helmets with different combinations of mounted devices were modelled in a validated human head-neck multi-body model to analyse their effects on the pilot's neck injury during simulated ejection. The probability of neck injury was evaluated and predicted using the Nij neck injury criteria and human injury risk curves, considering the tolerance of injury for upper and lower cervical segment. It was demonstrated that the helmet-mounted devices would increase the compression force and bending moment on cervical spine, especially for the lower cervical segments with higher Nij. In the cases with Night Vision Goggle, Nij of the lower cervical segment reached 0.54, which exceeded the requirement in aviation filed. For the cases with Visor, excessive extension occurred, resulting in a high Nij. The simulation results of this study could provide a reference for helmet and mounted devices design and offer a proposal for the protection of pilots during ejection.


Assuntos
Aviação , Lesões do Pescoço , Humanos , Dispositivos de Proteção da Cabeça , Lesões do Pescoço/prevenção & controle , Simulação por Computador , Vértebras Cervicais
11.
ACS Omega ; 7(45): 41107-41119, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36406586

RESUMO

Ionic liquid desulfurization is an effective method for achieving green and circulating desulfurization. To overcome the negative impact of the high viscosity of ionic liquids on the desulfurization process, an economical and efficient supported ionic liquid-triethanolamine acetate ionic liquid/silica (TAIL/SiO2) was prepared in this study. TAIL is synthesized using triethanolamine and acetic acid and subsequently loaded onto silica gel particles. The effects of the reaction temperature, humidity, silica particle size, and loading ratio on SO2 adsorption are investigated using a fixed-bed reactor. The results indicate that the surface of the silica gel loaded with ionic liquid formed uneven spherical clusters, and the aggregate volume increased with an increase in the loading ratio. The TAIL/SiO2 sulfur capacity could be effectively increased by increasing the loading ratio (exceeding 0.74 is unfavorable), decreasing the silica particle size, and reducing the reaction temperature and moisture content. The maximum sulfur capacity can reach 124.98 mg SO2/(g TAIL/SiO2) under experimental conditions, which is higher than that of activated carbon. The Bangham rate model effectively predicts the kinetics of the adsorption process of SO2.

12.
Comput Math Methods Med ; 2021: 9354202, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34938359

RESUMO

It has been deemed that the premetastatic niche (PMN) plays a critical role in facilitating bone metastasis of breast cancer cells. Tissue engineering scaffolds provide an advantageous environment to promote osteogenesis that may mimic the bony premetastatic niches (BPMNs). In this study, human mesenchymal stem cells (hMSCs) were seeded onto designed polycaprolactone/nanohydroxyapatite (PCL-nHA) scaffolds for osteogenic differentiation. Subsequently, a coculture system was used to establish the tissue-engineered BPMNs by culturing breast cancer cells, hMSCs, and osteoid-formed PCL-nHA scaffolds. Afterwards, a migration assay was used to investigate the recruitment of MDA-MB-231, MCF-7, and MDA-MB-453 cells to the BPMNs' supernatants. The cancer stem cell (CSC) properties of these migrated cells were investigated by flow cytometry. Our results showed that the mRNA expression levels of alkaline phosphatase (ALP), Osterix, runt-related transcription factor 2 (Runx2), and collagen type I alpha 1 (COL1A1) on the PCL-nHA scaffolds were dramatically increased compared to the PCL scaffolds on days 11, 18, and 32. The expression of CXCL12 in these BPMNs was increased gradually over coculturing time, and it may be a feasible marker for BPMNs. Furthermore, migration analysis results showed that the higher maturation of BPMNs collectively contributed to the creation of a more favorable niched site for the cancerous invasion. The subpopulation of breast cancer stem cells (BCSCs) was more likely to migrate to fertile BPMNs. The proportion of BCSCs in metastatic MDA-MB-231, MCF-7, and MDA-MB-453 cells were increased by approximately 63.47%, 149.48%, and 127.60%. The current study demonstrated that a designed tissue engineering scaffold can provide a novel method to create a bone-mimicking environment that serves as a useable platform to recapitulate the BPMNs and help interrogate the scheme of bone metastasis by breast cancer.


Assuntos
Neoplasias da Mama/patologia , Metástase Neoplásica/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Quimiocina CXCL12/metabolismo , Técnicas de Cocultura , Biologia Computacional , Durapatita , Feminino , Humanos , Células MCF-7 , Células-Tronco Mesenquimais/patologia , Nanoestruturas , Invasividade Neoplásica , Metástase Neoplásica/genética , Células-Tronco Neoplásicas/patologia , Osteogênese/genética , Poliésteres , Nicho de Células-Tronco , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Microambiente Tumoral
13.
Comput Biol Med ; 133: 104386, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33878515

RESUMO

BACKGROUND: Pedicle screws are widely used in fusion surgery, while screw loosening often occurrs. An auxetic structures based pedicle screw was proposed to improve the bone-screw fixation by radial expansion of the screw body under tensile force to resist pulling out. It was optimized to obtain excellent anti-pullout ability for a particular bone based on the biomechanical interaction between screw and surrounding bone. METHODS: The screw was designed based on re-entrant unit cells. The mechanical properties of it were adjusted by the wall thickness (t) and re-entrant angle (θ) of the unit cell, and characterized using finite element (FE) method. The designed screws were manufactured using 3D-printing, and Ti6Al4V as the materials. Subsequently, the pullout FE models were established, and verified by pulling the fabricated screws out of Sawbone blocks. The pulling out processes of screws from bone were simulated to explore the optimizing design of the screw. RESULTS: The mechanical properties of the screw could be adjusted in a wide range. The biomechanical interaction between the screw and bone can affect the anti-pullout performance of the screw. With an identical elastic modulus (E), better auxiticity of the screw, resulted in a better anti-pullout performance; while an appropriate E is the necessary condition for its excellent anti-pullout performance for a particular bone. CONCLUSION: Appropriate mechanical properties are necessary for the auxetic pedicle screw with excellent screw-bone fixation performance for a particular bone, which can be obtained by rationally designing the wall thickness and re-entrant angle of the unit cells.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Fenômenos Biomecânicos , Osso e Ossos , Vértebras Lombares , Teste de Materiais
14.
Cancer Biother Radiopharm ; 36(9): 737-752, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32343603

RESUMO

Background: Circular RNAs (circRNAs) have recently been reported to play essential roles in the progression of various cancers, including colorectal cancer (CRC). However, the roles of circRNA amyloid precursor-like protein 2 (circAPLP2) in CRC and its underlying mechanism have not been investigated. Materials and Methods: The expression levels of circAPLP2, microRNA-485-5p (miR-485-5p), and forkhead-box K1 (FOXK1) were determined by quantitative real-time polymerase chain reaction. Cell proliferation, apoptosis, migration, and invasion were assessed by methylthiazolyldiphenyl-tetrazolium bromide assay, flow cytometry, and transwell assay, respectively. Western blot assay was performed to measure the protein levels of proliferating cell nuclear antigen, Bcl-2, Bax, vimentin, E-cadherin, fibronectin, and FOXK1. The interaction between miR-485-5p and circAPLP2 or FOXK1 was predicted by starBase and verified by dual-luciferase reporter assay. A xenograft tumor model was established to confirm the functions of circAPLP2 in vivo. The lactate production was measured using lactate assay kit. Results: circAPLP2 expression was enhanced in CRC tissues and cells. circAPLP2 knockdown or miR-485-5p overexpression suppressed cell proliferation, migration, and invasion, whereas it promoted apoptosis in CRC cells, which was reversed by upregulating FOXK1. Moreover, miR-485-5p could directly bind to circAPLP2 and its downregulation reversed the suppressive effect of circAPLP2 knockdown on progression of CRC cells. In addition, FOXK1 was a downstream target of miR-485-5p. Furthermore, circAPLP2 modulated FOXK1 expression by sponging miR-485-5p in CRC cells. Besides, interference of circAPLP2 suppressed tumor growth in vivo and inhibited glycolysis in vitro by upregulating miR-485-5p and downregulating FOXK1. Conclusions: circAPLP2 knockdown inhibited CRC progression through regulating miR-485-5p/FOXK1 axis, providing a novel avenue for treatment of CRC.


Assuntos
Precursor de Proteína beta-Amiloide , Neoplasias Colorretais , Fatores de Transcrição Forkhead/metabolismo , MicroRNAs/metabolismo , Proteínas do Tecido Nervoso , Precursor de Proteína beta-Amiloide/antagonistas & inibidores , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Regulação para Baixo , Descoberta de Drogas , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , RNA Circular , Transdução de Sinais
15.
Biomed Microdevices ; 22(3): 53, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32780312

RESUMO

Compared with traditional drug delivery methods, transdermal drug delivery has many advantages in avoiding the side effects in gastrointestinal tract, reducing the fluctuations in drug concentration, and improving patients' compliance. Among them, electrically controlled drug delivery is a promising solution. This work presents a wireless, battery-free and wearable device with electrically controlled drug delivery capability. The electronic component of the device is a flexible circuit board with a temperature sensor and a near-field communication module. With the help of smartphone, the device could wirelessly obtain energy and implement data transmission. The drug delivery component is a paper-based electrode modified with polypyrrole, in which non-steroidal anti-inflammatory drug sodium salicylate was encapsulated. The applied potential for electrically controlled drug delivery was more negative than -0.6 V. The drug release dose and release rates could be controlled by applying potentials with different amplitudes and durations through this device. It provided a minimalized wearable transdermal drug delivery platform for monitoring diseases such as gout. This wearable device shows promising potential in develop closed-loop drug delivery and monitoring systems for the treatment of various diseases.


Assuntos
Sistemas de Liberação de Medicamentos/instrumentação , Eletricidade , Polímeros/química , Pirróis/química , Smartphone/instrumentação , Salicilato de Sódio/química , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio/instrumentação , Eletrodos , Papel
16.
Polymers (Basel) ; 12(7)2020 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-32707709

RESUMO

To improve the functional properties of starch-based films, chitin (CH) was prepared from shrimp shell powder and incorporated into corn starch (CS) matrix. Before blending, maleic anhydride (MA) was introduced as a cross-linker. Composite CS/MA-CH films were obtained by casting-evaporation approach. Mechanical property estimation showed that addition of 0-7 wt % MA-CH improved the tensile strength of starch films from 3.89 MPa to 9.32 MPa. Elongation at break of the films decreased with the addition of MA-CH, but the decrease was obviously reduced than previous studies. Morphology analysis revealed that MA-CH homogeneously dispersed in starch matrix and no cracks were found in the CS/MA-CH films. Incorporation of MA-CH decreased the water vapor permeability of starch films. The water uptake of the films was reduced when the dosage of MA-CH was below 5 wt %. Water contact angles of the starch films increased from 22° to 86° with 9 wt % MA-CH incorporation. Besides, the composite films showed better inhibition effect against Escherichia coli and Staphylococcus aureus than pure starch films.

17.
Biosens Bioelectron ; 137: 88-95, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31085402

RESUMO

Leptin is a vital biomarker of non-alcoholic fatty liver (NAFLD), and its evaluation of the concentration level in vivo is of great significance to NAFLD diagnosis. Therefore, it is pressing to develop a method for rapid and sensitive detection of leptin. This paper describes an environmentally friendly and label-free immunosensor based on porous graphene functionalized black phosphorus (PG-BP) composite to detect of leptin. The PG-BP was synthesized via strong coherent coupling between porous graphene (PG) surface plasmons and anisotropic black phosphorus (BP) localized surface plasmons, which made the electrochemical performance of PG and BP synergistic as well as increased the stability and conductive capability of BP material. The PG-BP modified electrodes was further prepared by gold nanoparticles, cysteamine, and glutaraldehyde in turn. Due to the cross-linking effect of glutaraldehyde, anti-leptin can be firmly fixed. These properties of the platform improved the conductive capability of the immunosensor and enhanced the load capacity of the proteins, thereby, the sensitivity of the immunosensor was significantly increased. Under the optimal conditions, the proposed immunosensor exhibited a wide linear range of 0.150-2500 pg/mL with a low detection limit of 0.036 pg/mL. The leptin immunosensor displayed excellent selectivity and anti-interference ability, which could be used for early screening and diagnosis of clinical NALFD.


Assuntos
Técnicas Biossensoriais , Grafite/química , Leptina/isolamento & purificação , Nanocompostos/química , Eletrodos , Humanos , Leptina/química , Fósforo/química
18.
J Biomater Sci Polym Ed ; 30(6): 462-485, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30755095

RESUMO

In this study, a solution chitosan fibroin emulsion with added Silver Nanoparticles (AgNPs) was freeze-dried to be the scaffold, and an asymmetric coating was formed on one side. PRP was loaded onto the composite scaffold using a secondary lyophilization technology to prepare the tissue engineering dressings. AgNPs were characterized using a transmission electron microscope. The morphologies of the composite dressing were examined under a scanning electron microscope. The silver content of the dressing was measured by inductively coupled plasma mass spectrometry. The asymmetric wettability of the composite dressing was demonstrated by water contact angle measurement. Relatively high porosity, favourable moisture retention capability and appropriate tensile strength were observed by measuring the physical and mechanical properties. Satisfactory antibacterial properties against various bacteria and microbial isolation performance were observed by the antibacterial effect analysis in vitro. The total protein slow-release property was measured using the BCA assay. Good biocompatibility and lower sensitization were examined both in vitro and in vivo. In addition, the healing effciency of the composite dressing on infected wound were examined in mice infected wound models. Analysis of wound healing rates, bacterial cultures of wound exudate, whole blood cell analysis and histological examination all showed satisfactory results. These results are demonstrated to provide a potential and possible pathway to promote wound tissue repair and regeneration.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bandagens/microbiologia , Portadores de Fármacos/química , Plasma Rico em Plaquetas/química , Plasma Rico em Plaquetas/metabolismo , Cicatrização/efeitos dos fármacos , Quitosana/química , Fibroínas/química , Fenômenos Mecânicos , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Prata/química , Molhabilidade
19.
Biosens Bioelectron ; 129: 284-291, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30245166

RESUMO

Silica nanopores have electron channels and ion channels interpenetrating each other, which prompt the use of this structure for creating efficient electronic devices. In this study, silica nanopores membrane modified screen printed electrodes were applied in a smartphone-based electrochemiluminescence system for nitroaromatic explosives detection. Universal serial bus-on the go (USB-OTG) and camera on smartphone were used as the electrical stimulation and luminescence capture, respectively. ⎕Multimode methods including (red-green-blue) RGB, (hue-saturation-brightness) HSB, and Gray were proposed for luminescence analysis. Specific polypeptides were immobilized on the nanopores modified electrodes for nitroaromatic explosives sensing. With positive-charged tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy)32+) as electrochemiluminescence label, the increase in luminescence was associated with the selective ion channels and the well-conductive electron channels in the negative-charged nanopores. Besides, on account of the large specific surface area, nanopores modified screen printed electrodes showed stable and uniform luminescence. Results showed that the nanopores-enhanced electrochemiluminescence on smartphone covered a linear dynamic range from 10-7 mg/mL to 10-3 mg/mL for nitroaromatic explosives detection with the detection limit of 2.3 × 10-9 mg/mL. Therefore, high-efficient photo-electricity conversion capabilities of nanopores made it a kind of promising platform for sensitive and stable electrochemiluminescence. Furthermore, smartphone-based electrochemiluminescence with disposable screen printed electrodes could facilitate the mobile monitoring of biochemical analytes in the fields of environment, security, and health.


Assuntos
Técnicas Biossensoriais/instrumentação , Dinitrobenzenos/análise , Substâncias Explosivas/análise , Nanoporos/ultraestrutura , Dióxido de Silício/química , Tolueno/análogos & derivados , Trinitrotolueno/análise , Técnicas Eletroquímicas/instrumentação , Eletrodos , Desenho de Equipamento , Limite de Detecção , Medições Luminescentes/instrumentação , Peptídeos/química , Smartphone , Tolueno/análise
20.
Biosens Bioelectron ; 117: 32-39, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29885577

RESUMO

Localized surface plasmon resonance (LSPR) induced charge separation were concentrated on the metal nanoparticles surface, which made it sensitive to the surface refractive index changes during optical sensing. Similarly, electrochemical detection was based on the electron transformation on the electrode surface. Herein, we fabricated a nanochip by decorating a nanocone-array substrate with gold nanoparticles and silver nanoparticles for dynamic electro-optical spectroscopy. Mercaptophenyl boronic acid (MPBA) was immobilized firmly on the nanochip by the metal-S bond for sensitive sialic acid sensing. Owing to the high stability of gold nanoparticles and the high sensitivity of silver nanoparticles, the nanochip showed good performance in LSPR detection with rich and high responses. Besides, the nanochip also showed sensitive electrical signals during electrochemical detection due to the excitation of the energetic charges from the nanoparticles surface to the reaction system. The dynamic electro-optical spectroscopy was based on a unique combination of LSPR and linear sweep voltammetry (LSV). On the one hand, electrochemical signals activated the electrons on the nanochip to promote the propagation and resonance of surface plasmon. On the other hand, LSPR concentrated the electrons on the nanochip surface, which made the electrons easily driven to enhance the current in electrochemical detection. Results showed that mutual promotion of electrochemical-LSPR on nanochip covered a linear dynamic range from 0.05 mM to 5 mM on selective sialic acid detection with a low detection limit of 17 µM. The synchronous amplification of the electro-optical response during electrochemical-LSPR, opened up a new perspective for efficient and sensitive biochemical detection.


Assuntos
Técnicas Biossensoriais/métodos , Eletroquímica , Dispositivos Lab-On-A-Chip , Ácido N-Acetilneuramínico/análise , Ressonância de Plasmônio de Superfície , Técnicas Biossensoriais/instrumentação , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Prata/química
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