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1.
BMC Genomics ; 25(1): 331, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565992

RESUMO

BACKGROUND: The pig (Sus Scrofa) is one of the oldest domesticated livestock species that has undergone extensive improvement through modern breeding. European breeds have advantages in lean meat development and highly-productive body type, whereas Asian breeds possess extraordinary fat deposition and reproductive performance. Consequently, Eurasian breeds have been extensively used to develop modern commercial breeds for fast-growing and high prolificacy. However, limited by the sequencing technology, the genome architecture of some nascent developed breeds and the human-mediated impact on their genomes are still unknown. RESULTS: Through whole-genome analysis of 178 individuals from an Asian locally developed pig breed, Beijing Black pig, and its two ancestors from two different continents, we found the pervasive inconsistent gene trees and species trees across the genome of Beijing Black pig, which suggests its introgressive hybrid origin. Interestingly, we discovered that this developed breed has more genetic relationships with European pigs and an unexpected introgression from Asian pigs to this breed, which indicated that human-mediated introgression could form the porcine genome architecture in a completely different type compared to native introgression. We identified 554 genomic regions occupied 63.30 Mb with signals of introgression from the Asian ancestry to Beijing Black pig, and the genes in these regions enriched in pathways associated with meat quality, fertility, and disease-resistant. Additionally, a proportion of 7.77% of genomic regions were recognized as regions that have been under selection. Moreover, combined with the results of a genome-wide association study for meat quality traits in the 1537 Beijing Black pig population, two important candidate genes related to meat quality traits were identified. DNAJC6 is related to intramuscular fat content and fat deposition, and RUFY4 is related to meat pH and tenderness. CONCLUSIONS: Our research provides insight for analyzing the origins of nascent developed breeds and genome-wide selection remaining in the developed breeds mediated by humans during modern breeding.


Assuntos
Introgressão Genética , Estudo de Associação Genômica Ampla , Humanos , Animais , Suínos/genética , Genoma , Genômica/métodos , Cruzamento , Polimorfismo de Nucleotídeo Único , Sus scrofa/genética , Seleção Genética
2.
ACS Appl Mater Interfaces ; 15(36): 42317-42328, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37640060

RESUMO

Elimination of tumor cells using carbonate nanomaterials with tumor microenvironment-responsive capacity has been explored as an effective strategy. However, their therapeutic outcomes are always compromised by the relatively low intratumoral accumulation and limited synthesis method. Herein, a novel kind of basic copper carbonate nanosheets was designed and prepared using a green synthesis method for photoacoustic imaging-guided tumor apoptosis and ferroptosis therapy. These nanosheets were synthesized with the assistance of dopamine and ammonium bicarbonate (NH4HCO3) and the loading of glucose oxidase (GOx). NH4HCO3 could not only provide an alkaline environment for the polymerization of dopamine but also supply carbonates for the growth of nanosheets. The formed nanosheets displayed good acid and near-infrared light responsiveness. After intercellular uptake, they could be degraded to release Cu2+ and GOx, generating hydroxyl radicals through a Cu+-mediated Fenton-like reaction, consuming glucose, up-regulating H2O2 levels, and down-regulating GSH levels. Tumor elimination could be achieved by hydroxyl radical-induced apoptosis and ferroptosis. More amusingly, this synthesis method can be extended to several kinds of mono-element and multi-element carbonate nanomaterials (e.g., Fe, Mn, and Co), showing great potential for further tumor theranostics.


Assuntos
Ferroptose , Neoplasias , Técnicas Fotoacústicas , Humanos , Cobre , Dopamina , Peróxido de Hidrogênio , Apoptose , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Glucose Oxidase , Radical Hidroxila , Microambiente Tumoral
3.
Colloids Surf B Biointerfaces ; 223: 113157, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36716658

RESUMO

Tumor-associated macrophages (TAMs)-mediated immunotherapy has attracted extensive attention in tumor elimination. However, the acidic tumor microenvironment (TME) severely limits the phenotype of TAMs to pro-tumoral M2 state, suppressing immune response efficacy against tumors. Herein, novel poly(acrylic acid) (PAA)-coated, doxorubicin (DOX)-loaded layered double hydroxide (LDH) nanosheets (NSs) were developed as deacidification agent to repolarize TAMs from pro-tumoral M2 to anti-tumoral M1 phenotype for tumor elimination through combined chemodynamic therapy and immunotherapy. When located in tumor regions, LDH-PAA@DOX NSs display good deacidification capacity to neutralize acidic TME, achieving the repolarization of TAMs to M1 phenotype and further activating CD8+ T cells. During the deacidification process, these NSs are acid-responsive and degrade to release Fe3+ and DOX. The former can be reduced to Fe2+ by intracellular glutathione, meanwhile disrupting the antioxidant defense system of tumor cells. The latter can damage tumor cells directly and further stimulate the production of hydrogen peroxide, providing abundant substrate for the Fenton reaction. Toxic hydroxyl radical is excessively produced through Fe2+-mediated Fenton reaction to cause intratumoral oxidative stress. In vivo data revealed that significant tumor elimination can be achieved under LDH-PAA@DOX treatment. This work not only provides a promising paradigm for neutralizing acidic TME using deacidification agent but also highlights the effectiveness of combined chemodynamic therapy and immunotherapy in tumor treatment.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Humanos , Macrófagos Associados a Tumor , Imunoterapia , Radical Hidroxila , Antioxidantes , Doxorrubicina , Peróxido de Hidrogênio , Microambiente Tumoral , Linhagem Celular Tumoral
5.
Nat Commun ; 13(1): 3822, 2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35780239

RESUMO

As the most well-known electrocatalyst for cathodic hydrogen evolution in water splitting electrolyzers, platinum is unfortunately inefficient for anodic oxygen evolution due to its over-binding with oxygen species and excessive dissolution in oxidative environment. Herein we show that single Pt atoms dispersed in cobalt hydrogen phosphate with an unique Pt(OH)(O3)/Co(P) coordination can achieve remarkable catalytic activity and stability for oxygen evolution. The catalyst yields a high turnover frequency (35.1 ± 5.2 s-1) and mass activity (69.5 ± 10.3 A mg-1) at an overpotential of 300 mV and excellent stability. Mechanistic studies elucidate that the superior catalytic performance of isolated Pt atoms herein stems from optimal binding energies of oxygen intermediate and also their strong electronic coupling with neighboring Co atoms that suppresses the formation of soluble Ptx>4 species. Alkaline water electrolyzers assembled with an ultralow Pt loading realizes an industrial-level current density of 1 A cm-2 at 1.8 volts with a high durability.

6.
Small Methods ; 6(6): e2101551, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35460201

RESUMO

Carbon dots (CDs) are one of the most popular photothermal agents (PTAs) as a noninvasive strategy for tumor treatment. However, because of the inherent dominant fluorescent emission, the CDs-based PTAs hardly achieve a single photothermal conversion, which causes low photothermal conversion efficiency and poor photothermal performance. In this regard, finding a new CDs-based material system to greatly restrain its fluorescence to enhance its photothermal conversion efficiency is highly required, however, it is still a grand challenge. Herein, a kind of Z-scheme CDs-based PTAs consisting of 2D ultrathin nonmetallic Bx C/C Janus quantum sheets (Bx C/C JQSs) is reported to greatly enhance the photothermal conversion efficiency. It is demonstrated that the heterogeneous growth of Z-scheme Bx C/C JQSs enables the NIR-driven quick injection of hot electrons from C into the conjugated Bx C, realizing a single conversion of light to heat, and resulting in a high photothermal conversion of 60.0% in NIR-II. Furthermore, these new Z-scheme Bx C/C-polyethylene glycol JQSs display outstanding biocompatibility and show effective tumor elimination outcome both in vitro and in vivo through the synergistic photothermal-immunotherapy in the NIR-II biowindow with undetectable harm to normal tissues.


Assuntos
Raios Infravermelhos , Fototerapia , Carbono , Linhagem Celular Tumoral , Imunoterapia , Fototerapia/métodos
7.
Adv Mater ; 32(38): e2000037, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32803803

RESUMO

Vulnerable atherosclerotic (AS) plaque is the major cause of cardiovascular death. However, clinical methods cannot directly identify the vulnerable AS plaque at molecule level. Herein, osteopontin antibody (OPN Ab) and NIR fluorescence molecules of ICG co-assembled Ti3 C2 nanosheets are reported as an advanced nanoprobe (OPN Ab/Ti3 C2 /ICG) with enhanced photoacoustic (PA) performance for direct and non-invasive in vivo visual imaging of vulnerable AS plaque. The designed OPN Ab/Ti3 C2 /ICG nanoprobes successfully realize obvious NIR fluorescence imaging toward foam cells as well as the vulnerable AS plaque slices. After intravenous injection of OPN Ab/Ti3 C2 /ICG nanoprobes into AS model mice, in vivo imaging results show a significantly enhanced PA signal in the aortic arch accumulated with vulnerable plaque, well indicating the remarkable feasibility of OPN Ab/Ti3 C2 /ICG nanoprobes to distinguish the vulnerable AS plaque. The proposed OPN Ab/Ti3 C2 /ICG nanoprobes not only overcome the clinical difficulty to differentiate vulnerable plaque, but also achieve the non-invasively specific in vivo imaging of vulnerable AS plaque at molecule level, greatly promoting the innovation of cardiovascular diagnosis technology.


Assuntos
Nanotecnologia/métodos , Técnicas Fotoacústicas/métodos , Placa Aterosclerótica/diagnóstico por imagem , Animais , Camundongos , Nanopartículas/química , Osteopontina/química
8.
Neurosci Bull ; 36(12): 1524-1537, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32710307

RESUMO

Following intrathecal injection of fluorescent tracers, ex vivo imaging of brain vibratome slices has been widely used to study the glymphatic system in the rodent brain. Tracer penetration into the brain is usually quantified by image-processing, even though this approach requires much time and manual operation. Here, we illustrate a simple protocol for the quantitative determination of glymphatic activity using spectrophotofluorometry. At specific time-points following intracisternal or intrastriatal injection of fluorescent tracers, certain brain regions and the spinal cord were harvested and tracers were extracted from the tissue. The intensity of tracers was analyzed spectrophotometrically and their concentrations were quantified from standard curves. Using this approach, the regional and dynamic delivery of subarachnoid CSF tracers into the brain parenchyma was assessed, and the clearance of tracers from the brain was also determined. Furthermore, the impairment of glymphatic influx in the brains of old mice was confirmed using our approach. Our method is more accurate and efficient than the imaging approach in terms of the quantitative determination of glymphatic activity, and this will be useful in preclinical studies.


Assuntos
Encéfalo/diagnóstico por imagem , Sistema Glinfático , Espectrometria de Fluorescência , Espectrofotometria , Animais , Líquido Cefalorraquidiano , Sistema Glinfático/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Camundongos
9.
Biomaterials ; 223: 119465, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31518842

RESUMO

Drug nanovehicles owning tumor microenvironment responsive and modulating capacities are highly demanding for effective tumor chemotherapy but still lack of exploration. Here, a kind of core-releasable satellite nanovehicles was rational constructed, which is composed of polydopamine (PDA) cores as photothermal agents and the carrier for small satellite nanoparticles (NPs) and drugs, G5Au NPs as the drug-loading satellites for deep tumor drug delivery and as catalase-like agents for relieving tumor hypoxia, doxorubicin (DOX) as the model chemotherapeutic drug loaded by both PDA and G5Au NPs, and polyethylene glycol (PEG) shells to improve biosafety. The developed drug-loaded nanovehicles (denoted as PDA-G5Au-PEG@DOX) can release G5Au satellites and DOX in stimuli-responsive manners. Thorough drug delivery in solid tumor can be realized via transporting DOX to the near-by area of and remote area from blood vessels by PDA and G5Au, respectively. Monitored by photoacoustic imaging and near-infrared fluorescence imaging, these PDA-G5Au-PEG@DOX NPs could accumulate in 4T1 tumor effectively. Under this guidance, significant tumor growth suppression could be achieved by the treatment of PDA-G5Au-PEG@DOX NPs plus laser without detectable side effects during the treatment period. The developed drug-loaded core-satellite nanovehicles with tumor microenvironment responsive/modulating capacities are of great potential in precise tumor treatments.


Assuntos
Antineoplásicos/uso terapêutico , Doxorrubicina/administração & dosagem , Nanomedicina/métodos , Neoplasias/tratamento farmacológico , Hipóxia Tumoral , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Hipertermia Induzida , Indóis/farmacologia , Ligantes , Camundongos , Nanopartículas/uso terapêutico , Transplante de Neoplasias , Oxigênio/metabolismo , Técnicas Fotoacústicas , Fototerapia , Polietilenoglicóis/química , Polímeros/farmacologia , Espectroscopia de Luz Próxima ao Infravermelho , Esferoides Celulares
10.
Langmuir ; 35(28): 9246-9254, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31251628

RESUMO

Design and construction of multifunctional theranostic nanoplatforms are still desired for cancer-effective treatment. Herein, a kind of polypyrrole (PPy)-based multifunctional nanocomposite was designed and successfully constructed for dual-model imaging and enhanced synergistic phototherapy against cancer cells. Through graphene oxide (GO) sheet coating, PPy nanoparticles (NPs) were effectively combined with polyethylene glycol chains, Au NPs, and IR820 molecules. The obtained PGPAI NPs showed promising ability for photoacoustic/computed tomography imaging. Under near-infrared light irradiation, the PPy core and IR820 molecule effectively generated heat and reactive oxygen species (ROS), respectively. Furthermore, the loaded Au NPs owning catalase-like activity produced oxygen by decomposing H2O2 (up-regulated in tumor region), enhancing the oxygen-dependent photodynamic therapy efficacy. The formed PGPAI NPs were also proved to own desirable photothermal conversion efficiency, photothermal stability, colloidal stability, cytocompatibility, and cellular internalization behaviors. Furthermore, cell assay demonstrated that PGPAI NPs displayed enhanced synergistic phototherapy efficacy against cancer cells. These developed multifunctional nanoplatforms are promising for effective cancer theranostic applications.


Assuntos
Nanocompostos/química , Imagem Óptica , Fototerapia , Polímeros/química , Pirróis/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , Tamanho da Partícula , Polímeros/farmacologia , Pirróis/farmacologia , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície
11.
Anal Biochem ; 577: 82-88, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31029675

RESUMO

Biothiols play critical roles in many biological processes and their aberrant is related to a variety of syndromes. A simple and reliable colorimetric method is developed in this work for biothiols detection based on an oxidase mimic, a metal organic framework (MOF) MIL-53(Fe), and a peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB). In this design, MIL-53(Fe) is utilized to catalyze the conversion of TMB to a blue colored 3,3',5,5'-tetramethylbenzidine diimine, which can be read on a spectrophotometer at 652 nm. The oxidation-induced blue color generation can be efficiently inhibited by biothiols, thus a colorimetric analytical method is proposed for biothiols detection based on the above system. Under optimal conditions, a linear relationship in a range from 1 to 100 µM and a limit of detection (LOD) at 120 nM are achieved with Cys as a model target. The developed platform is further applied to evaluate cellular biothiols in normal (RWPE-1) and cancer (LNCap) cell lines, revealing that the overall biothiols level in LNCap is much higher than that in RWPE-1. This work renders a powerful tool for identifying cancer cells in a simple manner for biomedical diagnosis associated with biothiols.


Assuntos
Cisteína/análise , Glutationa/análise , Homocisteína/análise , Benzidinas/química , Linhagem Celular , Colorimetria/métodos , Humanos , Estruturas Metalorgânicas/química
12.
Nanoscale ; 11(10): 4471-4477, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30801590

RESUMO

Electrochemical sensors actually involve an electrocatalytic process in efficient and selective energy conversion. In this work, we use different components to innovatively produce a core@cage material, in which the outer cage, iron phosphate, offers a high electrocatalytic ability to electrochemically oxidize NO, while the inner material, cuprous oxide, could absorb the intermediary HO- ions to kinetically promote NO oxidation for fast electron transfer, resulting in a strong synergistic effect. The unique core@cage structure also increases the active surface area and provides plenty of channels via the porous cage for significantly enhanced mass transport. The as-prepared core@cage NO sensor shows a high sensitivity of 326.09 µA cm-2 µM-1, which is the highest among the reported non-noble metal-based NO biosensors based on the electrooxidation scheme. A free-standing flexible NO sensor was further fabricated with the material for the in situ detection of NO released from cancer cells, demonstrating a low detection limit (0.45 nM) and a fast response time (0.8 s). This work holds great promise for its practical applications in the diagnosis or research of complicated biological processes, especially in real-time in situ detection approaches.


Assuntos
Cobre/química , Técnicas Eletroquímicas/métodos , Compostos de Ferro/química , Óxido Nítrico/análise , Fosfatos/química , Transporte de Elétrons , Humanos , Células MCF-7 , Porosidade
13.
Biomacromolecules ; 20(1): 401-411, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-30485741

RESUMO

Functionalized nanomaterials with near-infrared (NIR) responsive capacity are quite promising for theranostic treatment of tumors, but formation of NIR responsive nanomaterials with enhanced theranostic ability and excellent biocompatibility is still very challenging. Herein, PEGylated indocyanine green (ICG)-loaded polypyrrole nanoparticles (PPI NPs) were designed and successfully formed through selecting polydopamine as the linkage between each component, demonstrating enhanced NIR responsive theranostic ability against tumor. By combining in vitro cell study with in vivo assay, the formed PPI NPs were proven to be fantastically biocompatible while effectively internalization in HeLa cells and retention in HeLa tumor were demonstrated by in vitro flow cytometry/confocal measurement and in vivo photoacoustic imaging assay. With the guidance of photoacoustic imaging, successful photothermal ablation of tumor was achieved by treatment with PPI NPs plus laser, which was much more effective than the group treated with NPs free of ICG. The combined enhanced photoacoustic and photothermal effect is mainly ascribed to the functionalized polypyrrole nanoparticles, which could accumulate in the tumor site more effectively with a relatively longer retention time taking advantage of the nanomaterial-induced endothelial leakiness phenomenon. All these results demonstrating that this designed PPI NPs possessing enhanced NIR responsive property hold great promise for tumor NIR theranostic applications.


Assuntos
Hipertermia Induzida/métodos , Nanopartículas/química , Neoplasias Experimentais/terapia , Técnicas Fotoacústicas/métodos , Fototerapia/métodos , Animais , Células HeLa , Humanos , Verde de Indocianina/química , Indóis/química , Raios Infravermelhos/uso terapêutico , Camundongos , Camundongos Nus , Nanopartículas/efeitos adversos , Nanopartículas/uso terapêutico , Neoplasias Experimentais/diagnóstico por imagem , Polietilenoglicóis/química , Polímeros/química , Pirróis/química
14.
ACS Appl Mater Interfaces ; 9(40): 35040-35047, 2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-28920672

RESUMO

Metal-organic framework (MOF)-derived hollow cobalt sulfides have attracted extensive attention due to their porous shell that provides rich redox reactions for energy storage. However, their ultradispersed structure and the large size of MOF precursors result in relatively low conductivity, stability, and tap density. Therefore, the construction of an array of continuous hollow cages and tailoring of the inner cavity of MOF-derived materials is very effective for enhancing the electrochemical performance. Herein, we in situ assembled small Co-based zeolitic imidazolate framework (ZIF-67) on the both sides of negatively charged MnO2 nanosheets to fabricate a hierarchical sandwich-type composite with hollow cobalt sulfide nanocages/graphene-like MnO2. The graphene-like MnO2 nanosheets acted not only as a structure-directing agent to grow a ZIF-67 array but also as a promising electroactive material of electrochemical capacitors to provide capacitance. As an electrode material of supercapacitors, the as-prepared composites exhibit high specific capacitance (1635 F g-1 at 1 A g-1), great rate performance (reaching 1160 F g-1 at 10 A g-1), and excellent cycling stability (80% retention after 5000 cycles). The outstanding electrochemical properties of our designed materials can be attributed to the unique nanostructure that improved electrical conductivity, created more reactive active sites, and increased the diffusion pathway for electrolyte ions.

15.
Sci Rep ; 7(1): 3331, 2017 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-28611356

RESUMO

Recently, accumulating evidence has indicated that glucocorticoid-induced osteoporosis (GIOP) is closely related to oxidative stress and apoptosis. Alpha-lipoic acid (LA), a naturally endogenous anti-oxidant, possesses anti-oxidative and anti-apoptosis activities, implicating LA as a therapeutic agent for the treatment of GIOP. In this study, the osteogenesis-promoting effects of LA against GIOP were investigated and the mechanisms were further probed. Here, the results showed that LA inhibited oxidative stress, suppressed apoptosis and improved osteopenia by promoting the expression of osteogenesis markers, including ALP, COL-I, OCN, BMP-2, RUNX2 and OSX. Further study revealed that the osteogenesis-promoting effects of LA likely occur via the regulation of the NOX4, NF-kappaB, JNK and PI3K/AKT pathways. The present study indicated that LA may prevent GIOP and promote osteogenesis and might be a candidate for the treatment of GIOP.


Assuntos
Antioxidantes/farmacologia , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Transdução de Sinais , Ácido Tióctico/farmacologia , Animais , Antioxidantes/uso terapêutico , Linhagem Celular , Feminino , Glucocorticoides/toxicidade , MAP Quinase Quinase 4/metabolismo , NADPH Oxidase 4/metabolismo , NF-kappa B/metabolismo , Osteoporose/etiologia , Osteoporose/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Ácido Tióctico/uso terapêutico
16.
Chem Commun (Camb) ; 52(78): 11661-11664, 2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27711292

RESUMO

Novel nanocubic KTi2(PO4)3 was successfully fabricated via a facile hydrothermal method combined with a subsequent annealing treatment and further evaluated as an electrode material for potassium-ion batteries for the first time. For comparison, carbon-coated KTi2(PO4)3 obtained by a normal cane sugar-assisted method reveals improved electrochemical performances in potassium-ion batteries. This work may give a new insight into developing electrode materials for potassium-ion batteries.

17.
Anal Chim Acta ; 905: 72-8, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26755139

RESUMO

Electrochemical oxidation of glucose is the guarantee to realize nonenzymatic sensing of glucose, but greatly hindered by the slow kinetics of its oxidation process. Herein, various nanomaterials were designed as catalysts to accelerate glucose oxidation reaction. However, how to effectively build an excellent platform for promoting the glucose oxidation is still a great challenge. In our work, 1D CaMoO4 and NiMoO4 nanofibres with same morphologies and sub-microstructures were fabricated by electrospinning technique in the first time, and explored to modify the detection electrodes of nonenzymatic glucose sensors. The electrochemical results indicated that the NiMoO4 based sensor exhibited a good catalytic activity toward glucose including the low response potential (0.5 V), high sensitivity(193.8 µA mM(-1) cm(-2)) with a linear response region of 0.01-8 mM, low detection limit (4.6 µM) and fast response time (2 s), all of which are superior to the corresponding values of CaMoO4 nanofibres and even higher than those of most reported NiO and Co3O4 catalysts, which is due to the NiMoO4 nanofibres are not only advantageous to electron transfer, but can mediated the electrocatalytic reaction of glucose. This work should provide a new pathway for the design of advanced glucose catalysts for nonenzymatic sensor.


Assuntos
Glucose/química , Molibdênio/química , Nanofibras , Níquel/química , Catálise , Técnicas Eletroquímicas , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Oxirredução , Óxidos/química , Difração de Raios X
18.
Phys Chem Chem Phys ; 18(3): 1931-6, 2016 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26687451

RESUMO

In the present study, a simple strategy was developed to fabricate a new Bi2O3 nanostring-cluster hierarchical structure. Precursor microrods composed of Bi(C2O4)OH were initially grown under hydrothermal conditions. After calcination in air, Bi(C2O4)OH microrods were carved into unique string-cluster structures by the gas produced during the decomposition process. To explain the formation mechanism, the effects of pyrolysis temperature and time on the morphology of the as-prepared samples were investigated and are discussed in detail. It was discovered that the nanostring-cluster-structured Bi2O3 consists of thin nanoplatelet arrays, which is advantageous for glucose enzyme immobilization and for designing biosensors. The resulting Bi2O3 structure showed an excellent capability in the modification of electrode surfaces in biosensors by enhancing the sensitivity, with good specificity and response time. Such qualities of a biosensor are ideal characteristics for glucose sensing performance and allow for further explorations of its application in other fields.


Assuntos
Bismuto/química , Nanoestruturas , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura , Termogravimetria , Difração de Raios X
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