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1.
Food Chem ; 447: 139018, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38503067

RESUMO

Developing an accurate, cost-effective, reliable, and stable glucose detection sensor for the food industry poses a significant yet challenging endeavor. Herein, we present a silver nanoparticle-decorated titanium dioxide nanoribbon array on titanium plate (Ag@TiO2/TP) as an efficient electrode for non-enzymatic glucose detection in alkaline environments. Electrochemical evaluations of the Ag@TiO2/TP electrode reveal a broad linear response range (0.001 mM - 4 mM), high sensitivity (19,106 and 4264 µA mM-1 cm-2), rapid response time (6 s), and a notably low detection limit (0.18 µM, S/N = 3). Moreover, its efficacy in measuring glucose in beverage samples shows its practical applicability. The impressive performance and structural benefits of the Ag@TiO2/TP electrode highlight its potential in advancing electrochemical sensors for small molecule detection.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanotubos de Carbono , Nanopartículas Metálicas/química , Técnicas Eletroquímicas , Prata , Glucose/química , Eletrodos
2.
Small ; 20(13): e2307294, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37963858

RESUMO

The pursuit of stable and efficient electrocatalysts toward seawater oxidation is of great interest, yet it poses considerable challenges. Herein, the utilization of Cr-doped CoFe-layered double hydroxide nanosheet array is reported on nickel-foam (Cr-CoFe-LDH/NF) as an efficient electrocatalyst for oxygen evolution reaction in alkaline seawater. The Cr-CoFe-LDH/NF catalyst can achieve current densities of 500 and 1000 mA cm -2 with remarkably low overpotentials of only 334 and 369 mV, respectively. Furthermore, it maintains at least 100 h stability when operated at 500 mA cm-2.

3.
Biosens Bioelectron ; 248: 115968, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38150799

RESUMO

Screening for high-risk human papillomavirus (HPV) infection is one of the most important preventative measures for cervical cancer. However, fast, convenient, and low-cost HPV detection remains challenging, especially in resource-limited settings. Here, we report a portable all-in-one device (PAD) for point-of-care testing (POCT) for HPV16 and HPV18 DNA in cervical swabs. The PAD was engineered to integrate modules for extraction-free sample lysis, loop-mediated isothermal amplification (LAMP) with lyophilized reagent beads, and real-time colorimetric signal sensing into a single miniaturized device, considerably shortening the sample-to-result time to 15 min. The precision liquid handling in the completely sealed microfluidic chip is achieved by a uniquely designed pressure-balanced automatic liquid flow mechanism, thereby eliminating the need for manual manipulation of liquids and thus the risk of biohazards. The PAD employs an improved real-time colorimetric LAMP (rcLAMP) assay with a limit of detection (LOD) of 1 copy/µL, enabled by enhanced assay chemistry to maximize the reaction kinetics. To validate this device for clinical application, we tested 206 clinical cervical swab samples and obtained a sensitivity of 92.1% and a specificity of 99.0%. This custom PAD enabled by microfluidic and electronic engineering techniques can be configured for the simultaneous detection of HPV16 and HPV18 or other pathogens in point-of-care applications.


Assuntos
Técnicas Biossensoriais , Infecções por Papillomavirus , Feminino , Humanos , Microfluídica , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Colorimetria/métodos , Infecções por Papillomavirus/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/métodos , Testes Imediatos , DNA Viral/genética , Dispositivos Lab-On-A-Chip , Sensibilidade e Especificidade
4.
Nat Commun ; 14(1): 7539, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37985765

RESUMO

The rapid diagnosis of respiratory virus infection through breath and blow remains challenging. Here we develop a wireless, battery-free, multifunctional pathogenic infection diagnosis system (PIDS) for diagnosing SARS-CoV-2 infection and symptom severity by blow and breath within 110 s and 350 s, respectively. The accuracies reach to 100% and 92% for evaluating the infection and symptom severity of 42 participants, respectively. PIDS realizes simultaneous gaseous sample collection, biomarker identification, abnormal physical signs recording and machine learning analysis. We transform PIDS into other miniaturized wearable or portable electronic platforms that may widen the diagnostic modes at home, outdoors and public places. Collectively, we demonstrate a general-purpose technology for rapidly diagnosing respiratory pathogenic infection by breath and blow, alleviating the technical bottleneck of saliva and nasopharyngeal secretions. PIDS may serve as a complementary diagnostic tool for other point-of-care techniques and guide the symptomatic treatment of viral infections.


Assuntos
Líquidos Corporais , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/diagnóstico , Manejo de Espécimes , Saliva
5.
Immunobiology ; 228(6): 152741, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37716127

RESUMO

OBJECTIVE: To explore the association of single nucleotide polymorphisms (SNPs) in the transforming growth interacting factor (TGIF) gene with bone metabolism markers and rheumatoid arthritis (RA) susceptibility. METHODS: Three SNPs were genotyped in 155 RA patients and 168 healthy controls using high-resolution melting (HRM) analysis. The serum levels of osteocalcin, bone alkaline phosphatase (BALP), and ß type I collagen-crosslinked C telopeptide (ß-CTX) were detected using electrochemical luminescence in 108 patients randomly selected from the RA group. RESULTS: Genotype and allele frequency analysis showed that rs73620203 was associated with bone erosion in RA (P = 0.012 and P = 0.003, respectively), and individuals carrying the T allele for rs73620203 showed a decreased RA risk (OR = 0.59, 95% CI = 0.42-0.84; P = 0.003). In sex-specific analysis, the rs73620203 polymorphism was associated with susceptibility to RA in women (P = 0.022 and P = 0.006, respectively). In addition, RA patients with three genotypes at the rs73620203 locus showed significant differences in serum osteocalcin and BALP (P = 0.006 and P = 0.037, respectively). Haplotype analysis revealed that the haploid ATG and GCA frequencies were significantly lower in the RA group (P = 0.036, OR = 0.693; P = 0.002, OR = 0.189, respectively), while the haploid ACA frequency of the RA group was enhanced (P < 0.01, OR = 5.058). CONCLUSION: Our study provides the first evidence that rs73620203 is associated with RA susceptibility and the relationship between TGIF gene SNPs and the regulation of bone metabolism in RA patients.


Assuntos
Artrite Reumatoide , Predisposição Genética para Doença , Feminino , Humanos , Masculino , Alelos , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/genética , Estudos de Casos e Controles , China/epidemiologia , Frequência do Gene , Genótipo , Osteocalcina/genética , Polimorfismo de Nucleotídeo Único
6.
Chem Commun (Camb) ; 59(59): 9017-9028, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37409494

RESUMO

Electrochemical CO2 reduction into value-added chemicals represents an attractive and promising approach to capitalize on the abundant CO2 present in the atmosphere. This reaction, however, is hampered by low energy efficiency and selectivity owing to competition from hydrogen evolution reaction and multiple-electron transfer processes. Therefore, there is a pressing need to develop efficient yet cost-effective electrocatalysts to facilitate practical applications. Sn-based electrocatalysts have gained increasing attention in this active field due to their outstanding merits such as abundance, non-toxicity, and environmental friendliness. This review provides a comprehensive overview of recent advances in Sn-based catalysts for the CO2 reduction reaction (CO2RR), beginning with a brief introduction to the CO2RR mechanism. Subsequently, the CO2RR performance of various Sn-based catalysts with different structures is discussed. The article concludes by addressing the existing challenges and offering personal perspectives on the future prospects in this exciting research area.

7.
Anal Chem ; 95(32): 11978-11987, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37494597

RESUMO

The development of an array for high-throughput and logical analysis of biomarkers is significant for disease diagnosis. DNA-templated copper nanoclusters (CuNCs) have a strong potential to serve as a label-free photoluminescence source in array platforms, but their luminescent stability and sensitivity need to be improved. Herein, we report a facile, sensitive, and robust biomimetic array assay by integrating with stable luminescent CuNCs and entropy-driven nanomachine (EDN). In this strategy, the luminescent stability of CuNCs was improved by adding fructose in CuNCs synthesis to offer a reliable label-free signal. Meanwhile, the DNA template for CuNCs synthesis was introduced into EDN with excellent signal amplification ability, in which the reaction triggered by target miRNA would cause the blunt/protruding conformation change of 3'-terminus accompanied by the production or loss of luminescence. In addition, a biomimetic array fabricated by photonic crystals (PCs) physically enhanced the emitted luminescent signal of CuNCs and achieved high-throughput signal readout by a microplate reader. The proposed assay can isothermally detect as low as 4.5 pM of miR-21. Moreover, the logical EDN was constructed to achieve logical analysis of multiple miRNAs by "AND" or "OR" logic gate operation. Therefore, the proposed assay has the advantages of label-free property, high sensitivity, flexible design, and high-throughput analysis, which provides ideas for developing a new generation of facile and smart platforms in the fields of biological analysis and clinical application.


Assuntos
Nanopartículas Metálicas , MicroRNAs , Luminescência , DNA/química , Cobre/química , Biomimética , Entropia , MicroRNAs/análise , Nanopartículas Metálicas/química , Espectrometria de Fluorescência
8.
Inorg Chem ; 62(30): 11746-11750, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37449955

RESUMO

Constructing efficient and low-cost oxygen evolution reaction (OER) catalysts operating in seawater is essential for green hydrogen production but remains a great challenge. In this study, we report an iron doped cobalt carbonate hydroxide nanowire array on nickel foam (Fe-CoCH/NF) as a high-efficiency OER electrocatalyst. In alkaline seawater, such Fe-CoCH/NF demands an overpotential of 387 mV to drive 500 mA cm-2, superior to that of CoCH/NF (597 mV). Moreover, it achieves excellent electrochemical and structural stability in alkaline seawater.

9.
Langmuir ; 26(7): 4563-6, 2010 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-20180563

RESUMO

Chemical functionalization of silicon oxide (SiO(2)) surfaces with silane molecules is an important technique for a variety of device and sensor applications. Quality control of self-assembled monolayers (SAMs) is difficult to achieve because of the lack of a direct measure for newly formed interfacial Si-O bonds. Herein we report a sensitive measure of the bonding interface between the SAM and SiO(2), whereby the longitudinal optical (LO) phonon mode of SiO(2) provides a high level of selectivity for the characterization of newly formed interfacial bonds. The intensity and spectral position of the LO peak, observed upon silanization of a variety of silane molecules, are shown to be reliable fingerprints of formation of interfacial bonds that effectively extend the Si-O network after SAM formation. While the IR absorption intensities of functional groups (e.g., >C=O, CH(2)/CH(3)) depend on the nature of the films, the blue-shift and intensity increase of the LO phonon mode are common to all silane molecules investigated and their magnitude is associated with the creation of interfacial bonds only. Moreover, results from this study demonstrate the ability of the LO phonon mode to analyze the silanization kinetics of SiO(2) surfaces, which provides mechanistic insights on the self-assembly process to help achieve a stable and high quality SAM.

10.
ACS Nano ; 3(10): 3085-90, 2009 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-19731931

RESUMO

Control of polymer morphology and chain orientation is of great importance in organic solar cells and field effect transistors (OFETs). Here we report the use of nanoimprint lithography to fabricate large-area, high-density, and ordered nanostructures in conjugated polymer poly(3-hexylthiophene) or P3HT, and also to simultaneously control 3D chain alignment within these P3HT nanostructures. Out-of-plane and in-plane grazing incident X-ray diffraction were used to determine the chain orientation in the imprinted P3HT nanostructures, which shows a strong dependence on their geometry (gratings or pillars). Vertical chain alignment was observed in both nanogratings and nanopillars, indicating strong potential to improve charge transport and optical properties for solar cells in comparison to bulk heterojunction structure. For P3HT nanogratings, pi-pi stacking along the grating direction with an angular distribution of +/-20 degrees was found, which is favorable for OFETs. We propose the chain alignment is induced by the nanoconfinement during nanoimprinting via pi-pi interaction and hydrophobic interaction between polymer chain and mold surfaces.

11.
Biomed Microdevices ; 11(6): 1205-12, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19629700

RESUMO

With strides in stem cell biology, cell engineering and molecular therapy, the transplantation of cells to produce therapeutic molecules endogenously is an attractive and achievable alternative to the use of exogenous drugs. The encapsulation of such cell transplants in semi-permeable, nanoporous constructs is often required to protect them from immune attack and to prevent their proliferation in the host. However, effective graft immunoisolation has been mostly elusive owing to the absence of a high-throughput method to create precisely controlled, high-aspect-ratio nanopores. To address the clinical need for effective cell encapsulation and immunoisolation, we devised a biocompatible cell-encapsulating microcontainer and a method to create highly anisotropic nanopores in the microcontainer's surface. To evaluate the efficacy of these nanopores in oxygenating the encapsulated cells, we engineered 9L rat glioma cells to bioluminesce under hypoxic conditions. The methods described above should aid in evaluating the long term survival and efficacy of cellular grafts.


Assuntos
Transplante de Células/métodos , Oxigênio/metabolismo , Animais , Células Cultivadas , Porosidade , Ratos
13.
Langmuir ; 22(26): 11279-83, 2006 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-17154616

RESUMO

We demonstrate a guided self-assembly approach to the fabrication of DNA nanostructures on silicon substrates. DNA oligonucleotides self-assemble into "rafts" 8 x 37 x 2 nm in size. The rafts bind to cationic SAMs on silicon wafers. Electron-beam lithography of a thin poly(methyl methacrylate) (PMMA) resist layer was used to define trenches, and (3-aminopropyl)triethoxysilane (APTES), a cationic SAM precursor, was deposited from aqueous solution onto the exposed silicon dioxide at the trench bottoms. The remaining PMMA can be cleanly stripped off with dichloromethane, leaving APTES layers 0.7-1.2 nm in thickness and 110 nm in width. DNA rafts bind selectively to the resulting APTES stripes. The coverage of DNA rafts on adjacent areas of silicon dioxide is 20 times lower than on the APTES stripes. The topographic features of the rafts, measured by AFM, are identical to those of rafts deposited on wide-area SAMs. Binding to the APTES stripes appears to be very strong as indicated by "jamming" of the rafts at a saturation coverage of 42% and the stability to repeated AFM scanning in air.


Assuntos
Nanoestruturas/química , Oligodesoxirribonucleotídeos/química , Polimetil Metacrilato/química , Silanos/química , Microscopia de Força Atômica/métodos , Nanoestruturas/ultraestrutura , Propilaminas , Propriedades de Superfície
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