Single-Step Formation of Ni Nanoparticle-Modified Graphene–Diamond Hybrid Electrodes for Electrochemical Glucose Detection

The development of accurate, reliable devices for glucose detection has drawn much attention from the scientific community over the past few years. Here, we report a single-step method to fabricate Ni nanoparticle-modified graphene–diamond hybrid electrodes via a catalytic thermal treatment, by which the graphene layers are directly grown on the diamond surface using Ni thin film as a catalyst, meanwhile, Ni nanoparticles are formed in situ on the graphene surface due to dewetting behavior. The good interface between the Ni nanoparticles and the graphene guarantees efficient charge transfer during electrochemical detection. The fabricated electrodes exhibit good glucose sensing performance with a low detection limit of 2 μM and a linear detection range between 2 μM–1 mM. In addition, this sensor shows great selectivity, suggesting potential applications for sensitive and accurate monitoring of glucose in human blood.

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A NiFe Alloy Reduced on Graphene Oxide for Electrochemical Nonenzymatic Glucose Sensing

Sensors ◽

10.3390/s18113972 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3972 ◽

Cited By ~ 5

Author(s):

Zhe-Peng Deng ◽

Yu Sun ◽

Yong-Cheng Wang ◽

Jian-De Gao

Keyword(s):

Graphene Oxide ◽

High Selectivity ◽

Glucose Sensing ◽

Glucose Detection ◽

Ni Nanoparticles ◽

X Ray Diffraction ◽

Modified Glassy Carbon Electrode ◽

X Ray ◽

Transmission Electron ◽

Measurement Results

A NiFe alloy nanoparticle/graphene oxide hybrid (NiFe/GO) was prepared for electrochemical glucose sensing. The as-prepared NiFe/GO hybrid was characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The results indicated that NiFe alloy nanoparticles can be successfully deposited on GO. The electrochemical glucose sensing performance of the as-prepared NiFe/GO hybrid was studied by cyclic voltammetry and amperometric measurement. Results showed that the NiFe/GO-modified glassy carbon electrode had sensitivity of 173 μA mM−1 cm−2 for glucose sensing with a linear range up to 5 mM, which is superior to that of commonly used Ni nanoparticles. Furthermore, high selectivity for glucose detection could be achieved by the NiFe/GO hybrid. All the results demonstrated that the NiFe/GO hybrid has promise for application in electrochemical glucose sensing.

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Facile Synthesis of Carbon Quantum Dots by Plasma-liquid Interaction Method

Communications in Physics ◽

10.15625/0868-3166/27/4/10867 ◽

2018 ◽

Vol 27 (4) ◽

pp. 311 ◽

Cited By ~ 2

Author(s):

Do Hoang Tung ◽

Tran Thi Thuong ◽

Nguyen Dinh Cong ◽

Nguyen Thanh Liem ◽

Nguyen Van Kha ◽

...

Keyword(s):

Quantum Dots ◽

Water Solubility ◽

Carbon Quantum Dots ◽

Single Step ◽

Excitation Wavelength ◽

Interaction Method ◽

Step Method ◽

Photo Catalysis ◽

Chemical Inertness ◽

Potential Applications

Carbon quantum dots (CQDs) are a novel type of fluorescent nano-materials with various unique properties. They are recently attracting enormous interest due to their superiority in water solubility, chemical inertness, low toxicity, ease of functionalization as well as resistance to photo-bleaching and potential applications in biomedical indication, photo-catalysis, energy conversion, optoelectronics, and sensing. In this work, we present a facile and environmentally friendly synthesis of CQDs based on plasma - liquid interaction method. This is a single-step method and does not use toxic chemicals. The size distribution of obtained CQDs is rather uniform at approximately 3 nm. The emission peak of CQDs shifts from 427 nm to 523 nm as the excitation wavelength is varied from 340 nm to 460 nm. The non-equilibrium reactive chemistry of plasma liquid interaction is responsible for acceleration of the CQDs formation process.

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Purification of Urokinase from Complex Mixtures Using Immobilized Monoclonal Antibody Against Urokinase Light Chain

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657308 ◽

1983 ◽

Vol 49 (01) ◽

pp. 024-027 ◽

Cited By ~ 20

Author(s):

David Vetterlein ◽

Gary J Calton

Keyword(s):

Monoclonal Antibody ◽

Light Chain ◽

Culture Media ◽

Biological Fluids ◽

Single Step ◽

High Yield ◽

Step Method ◽

Commercial Preparation ◽

E Coli ◽

Tissue Culture Media

SummaryThe preparation of a monoclonal antibody (MAB) against high molecular weight (HMW) urokinase light chain (20,000 Mr) is described. This MAB was immobilized and the resulting immunosorbent was used to isolate urokinase starting with an impure commercial preparation, fresh urine, spent tissue culture media, or E. coli broth without preliminary dialysis or concentration steps. Monospecific antibodies appear to provide a rapid single step method of purifying urokinase, in high yield, from a variety of biological fluids.

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Ratiometric Fluorescent Biosensors for Glucose and Lactate Using an Oxygen-Sensing Membrane

Biosensors ◽

10.3390/bios11070208 ◽

2021 ◽

Vol 11 (7) ◽

pp. 208

Author(s):

Hong Dinh Duong ◽

Jong Il Rhee

Keyword(s):

Limit Of Detection ◽

Oxygen Sensing ◽

High Sensitivity ◽

Glucose Sensing ◽

Oxidation Reactions ◽

Lactate Oxidase ◽

Lactate Oxidation ◽

Detection Range ◽

Quenching Effect ◽

Sensing Membrane

In this study, ratiometric fluorescent glucose and lactate biosensors were developed using a ratiometric fluorescent oxygen-sensing membrane immobilized with glucose oxidase (GOD) or lactate oxidase (LOX). Herein, the ratiometric fluorescent oxygen-sensing membrane was fabricated with the ratio of two emission wavelengths of platinum meso-tetra (pentafluorophenyl) porphyrin (PtP) doped in polystyrene particles and coumarin 6 (C6) captured into silica particles. The operation mechanism of the sensing membranes was based on (i) the fluorescence quenching effect of the PtP dye by oxygen molecules, and (ii) the consumption of oxygen levels in the glucose or lactate oxidation reactions under the catalysis of GOD or LOX. The ratiometric fluorescent glucose-sensing membrane showed high sensitivity to glucose in the range of 0.1–2 mM, with a limit of detection (LOD) of 0.031 mM, whereas the ratiometric fluorescent lactate-sensing membrane showed the linear detection range of 0.1–0.8 mM, with an LOD of 0.06 mM. These sensing membranes also showed good selectivity, fast reversibility, and stability over long-term use. They were applied to detect glucose and lactate in artificial human serum, and they provided reliable measurement results.

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Composite Poly(vinyl alcohol)-Based Nanofibers Embedding Differently-Shaped Gold Nanoparticles: Preparation and Characterization

Polymers ◽

10.3390/polym13101604 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1604

Author(s):

Andrea Dodero ◽

Maila Castellano ◽

Paola Lova ◽

Massimo Ottonelli ◽

Elisabetta Brunengo ◽

...

Keyword(s):

Vinyl Alcohol ◽

Ad Hoc ◽

Chemical Reduction ◽

Chemical Properties ◽

Single Step ◽

Gold Nanostructures ◽

Poly Vinyl Alcohol ◽

Spherical Nanoparticles ◽

Potential Applications ◽

New Perspective

Poly(vinyl alcohol) nanofibrous mats containing ad hoc synthesized gold nanostructures were prepared via a single-step electrospinning procedure and investigated as a novel composite platform with several potential applications. Specifically, the effect of differently shaped and sized gold nanostructures on the resulting mat physical-chemical properties was investigated. In detail, nearly spherical nanoparticles and nanorods were first synthesized through a chemical reduction of gold precursors in water by using (hexadecyl)trimethylammonium bromide as the stabilizing agent. These nanostructures were then dispersed in poly(vinyl alcohol) aqueous solutions to prepare nanofibrous mats, which were then stabilized via a humble thermal treatment able to enhance their thermal stability and water resistance. Remarkably, the nanostructure type was proven to influence the mesh morphology, with the small spherical nanoparticles and the large nanorods leading to thinner well defined or bigger defect-rich nanofibers, respectively. Finally, the good mechanical properties shown by the prepared composite mats suggest their ease of handleability thereby opening new perspective applications.

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Laser-Induced Deposition of Plasmonic Ag and Pt Nanoparticles, and Periodic Arrays

Materials ◽

10.3390/ma14010010 ◽

2020 ◽

Vol 14 (1) ◽

pp. 10

Author(s):

Daria V. Mamonova ◽

Anna A. Vasileva ◽

Yuri V. Petrov ◽

Denis V. Danilov ◽

Ilya E. Kolesnikov ◽

...

Keyword(s):

Substrate Surface ◽

Pt Nanoparticles ◽

Single Step ◽

X Ray Diffraction ◽

Ag Nps ◽

X Ray ◽

Periodic Arrays ◽

Potential Applications ◽

Surface Decoration ◽

Wide Potential

Surfaces functionalized with metal nanoparticles (NPs) are of great interest due to their wide potential applications in sensing, biomedicine, nanophotonics, etc. However, the precisely controllable decoration with plasmonic nanoparticles requires sophisticated techniques that are often multistep and complex. Here, we present a laser-induced deposition (LID) approach allowing for single-step surface decoration with NPs of controllable composition, morphology, and spatial distribution. The formation of Ag, Pt, and mixed Ag-Pt nanoparticles on a substrate surface was successfully demonstrated as a result of the LID process from commercially available precursors. The deposited nanoparticles were characterized with SEM, TEM, EDX, X-ray diffraction, and UV-VIS absorption spectroscopy, which confirmed the formation of crystalline nanoparticles of Pt (3–5 nm) and Ag (ca. 100 nm) with plasmonic properties. The advantageous features of the LID process allow us to demonstrate the spatially selective deposition of plasmonic NPs in a laser interference pattern, and thereby, the formation of periodic arrays of Ag NPs forming diffraction grating

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High-resolution limited-angle phase tomography of dense layered objects using deep neural networks

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1821378116 ◽

2019 ◽

Vol 116 (40) ◽

pp. 19848-19856 ◽

Cited By ~ 12

Author(s):

Alexandre Goy ◽

Girish Rughoobur ◽

Shuai Li ◽

Kwabena Arthur ◽

Akintunde I. Akinwande ◽

...

Keyword(s):

Integrated Circuit ◽

Deep Neural Networks ◽

Tomographic Reconstruction ◽

Synthetic Data ◽

Single Step ◽

Training Set ◽

Step Method ◽

3 Dimensional ◽

Dimensional Reconstruction ◽

Optical Domain

We present a machine learning-based method for tomographic reconstruction of dense layered objects, with range of projection angles limited to ±10○. Whereas previous approaches to phase tomography generally require 2 steps, first to retrieve phase projections from intensity projections and then to perform tomographic reconstruction on the retrieved phase projections, in our work a physics-informed preprocessor followed by a deep neural network (DNN) conduct the 3-dimensional reconstruction directly from the intensity projections. We demonstrate this single-step method experimentally in the visible optical domain on a scaled-up integrated circuit phantom. We show that even under conditions of highly attenuated photon fluxes a DNN trained only on synthetic data can be used to successfully reconstruct physical samples disjoint from the synthetic training set. Thus, the need for producing a large number of physical examples for training is ameliorated. The method is generally applicable to tomography with electromagnetic or other types of radiation at all bands.

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