Electrochemical Synthesis of Zinc Oxide Nanostructures on Flexible Substrate and Application as an Electrochemical Immunoglobulin-G Immunosensor

Immunoglobulin G (IgG), a type of antibody, represents approximately 75% of serum antibodies in humans, and is the most common type of antibody found in blood circulation Consequently, the development of simple, fast and reliable systems for IgG detection are of considerable interest which can be achieved using electrochemical sandwich-type immunosensors. In this study we have developed an immunosensor sub-strate using an inexpensive and very simple fabrication method based on ZnO nanorods obtained through the electrodeposition of ZnO. The ZnO nanorods were treated by electrodepositing a layer of reduced gra-phene oxide to ensure an easy immobilization of the antibodies. On this substrate, the sandwich configura-tion of the immunosensor was built through different incubation steps, that were all optimized. The im-munosensor is electrochemically active thanks to the presence of gold nanoparticles tagging the secondary antibody, therefore it has been used to measure the current density of the hydrogen development reaction which is indirectly linked to the concentration of H-IgG antigens. In this way the calibration curve was constructed obtaining a linear range of 1-100 ng / ml with a detection limit of few ng / mL and good sensi-tivity.

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Crystal Structural Studies of ZnO Nanorods and their Band Gaps

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.938.71 ◽

2014 ◽

Vol 938 ◽

pp. 71-75

Author(s):

Muhd Firdaus Kasim ◽

Norlida Kamarulzaman ◽

Suraya Ahmad Kamil

Keyword(s):

Electron Microscopy ◽

Zinc Oxide ◽

Zno Nanorods ◽

Chelating Agent ◽

Band Gaps ◽

Zinc Oxide Nanostructures ◽

X Ray Diffraction ◽

Soft Chemistry ◽

Oxide Nanostructures ◽

Vis Spectroscopy

Zinc oxide nanostructures have been done by many scientists but amongst the soft chemistry methods, chelating agents are normally used. In this work zinc oxide nanostructures have been synthesized using a soft chemistry method without using a chelating agent. The precursor were annealed at various temperatures of 400 °C, 500 °C, 600 °C, 700 °C, 800 °C and 1200 °C for 24 h. Nanostructures are found with rod-like shapes and they are compared with larger oval morphology. X-Ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), and UV-Vis spectroscopy were used for characterization. XRD results confirm that all peaks were pure and single phase without the presence of any impurities. It was found from electron microscopy results that the morphology of the materials annealed at 400 °C possesses nanorod shape and as the calcination temperature increases, the material consists of mixed rod, spherical and oval shapes. The aspect ratio of the materials decreases when the annealing temperature increases. The absorption edges of the materials annealed at higher temperatures show a red-shift implying that narrowing of the band gaps occur in the materials. Band gap were evaluated and found to be between 3.32 to 3.19 eV.

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Zinc Oxide Nanorod Growth on Au-coated Silverwire

Journal of New Materials for Electrochemical Systems ◽

10.14447/jnmes.v20i2.296 ◽

2017 ◽

Vol 20 (2) ◽

pp. 049-051

Author(s):

Hsiang Chen ◽

Wei Ming Su ◽

Yu-Tzu Chen ◽

Chien-Cheng Lu ◽

Cheng-Yuan Weng

Keyword(s):

Zinc Oxide ◽

Zno Nanorods ◽

Zno Nanostructures ◽

Zinc Oxide Nanostructures ◽

Pure Silver ◽

Oxide Nanostructures ◽

Zno Nanoflakes ◽

Coated Layer ◽

Nanorod Growth ◽

Multiple Analysis

In this study, zinc oxide nanostructures were grown on gold-coated silver wires by hydrothermal method. Multiple analyses on these nanostructures were performed to understand the structure and optical properties of zinc oxide on Au-plated silver wires, Owing to the Au-coated layer, ZnO nanorods could appear rather than ZnO nanoflakes on pure silver wires. Moreover, The deposited gold layer could vary zinc oxide nanostructures to nanorods The multiple analysis shows that lying flat ZnO structures with weak (002) crystalline structures and more defects could appear on the silver wire rather than ZnO nanostructures on pure silver wires.

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Influence of Ammonia Solution on Zinc Oxide Nanostructures by Hydrothermal Growth

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.875-877.1549 ◽

2014 ◽

Vol 875-877 ◽

pp. 1549-1553 ◽

Cited By ~ 1

Author(s):

Z.B. Huang ◽

X.P. Zou ◽

G.Q. Yang ◽

X.M. Lv ◽

C.L. Wei ◽

...

Keyword(s):

Zinc Oxide ◽

Tin Oxide ◽

Indium Tin Oxide ◽

Zno Nanorods ◽

Precursor Solution ◽

Ammonia Solution ◽

Zinc Nitrate ◽

Hydrothermal Growth ◽

Zinc Oxide Nanostructures ◽

Oxide Nanostructures

In previous work, ZnO nanorods and nanoflowers were synthesized on indium-tin-oxide (ITO) substrates by hydrothermal growth at low temperature ,using the different concentrations of equimolar (1:1) zinc nitrate Zn (NO3)26H2O and methenamine (C6H12N4) mixed as precursors solution, and adding ammonia solution to control the pH levels. In this paper, for comparison, the same experiment without ammonia solution was also discussed. SEM, XRD were utilized to characterize morphologies and crystal structures of ZnO. It was indicated that the pH of precursor solution leads to the significantly changes in the nanostructured ZnO. Besides, a hierarchical structure of some of the micro/nanotubes was obtained .The possible growth mechanism is discussed in this work.

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Growth of Zinc Oxide Nanostructures on Electrochemically-Etched p-Type Silicon(100) Substrate by Chemical Bath Deposition Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.548-549.358 ◽

2014 ◽

Vol 548-549 ◽

pp. 358-362 ◽

Cited By ~ 1

Author(s):

Haziel Marie D. Paculba ◽

Arnold C. Alguno

Keyword(s):

Chemical Bath Deposition ◽

Electrochemical Etching ◽

Zno Nanorods ◽

Chemical Bath Deposition Method ◽

Basic Solution ◽

Deposition Method ◽

Zinc Oxide Nanostructures ◽

X Ray ◽

Oxide Nanostructures ◽

P Type

ZnO nanostructures were successfully grown on electrochemically etched p-type Si (100) substrate via chemical bath deposition method under basic solution. These nanostructures are characterized through scanning electron microscopy – energy dispersive X-ray spectroscopy (SEM-EDS) and ultraviolet-visible spectroscopy (UV-Vis). SEM results revealed that the density of the ZnO nanorods can be controlled by changing the surface morphology of the substrate via electrochemical etching process. At around 200-400 nm, the reflectance intensity of ZnO is significantly decreased as the density of the nanorods increases. Discussion on the possible growth mechanism of ZnO on etched Si during deposition is also presented.

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