scholarly journals Non-perpendicular incidence angle of cold atmospheric-pressure plasma treatment for fabrication of silver-based surface plasmon resonance biosensor for detection of Escherichia coli in water

2021 ◽  
Author(s):  
Maryam Hosseinpour ◽  
Akbar Zendehnam ◽  
Seyedeh Mehri Hamidi Sangdehi ◽  
Hamidreza Ghomi Marzdashti
Keyword(s):  
Thin Film ◽  
Escherichia Coli ◽  
Glass Substrate ◽  
Silver Film ◽  
Incidence Angle ◽  
Film Surface ◽  
Distilled Water ◽  
Spr Biosensor ◽  
Silver Thin Film ◽  
Perpendicular Incidence

Abstract In this study, for the first time, to our knowledge, a biosensor was produced using cold atmospheric plasma (CAP) treatment of silver thin film surface with non-perpendicular incidence angle for identification of Escherichia coli in the distilled water. Field emission scanning electron microscopy (FESEM) exhibits that before deposition, non-perpendicular CAP treatment of glass surface substrate leads to the production of pinhole-free silver thin film. The results of atomic force microscopy (AFM), and curve fitting show that non-perpendicular CAP treatment of this pinhole-free silver thin film indicates to the appearance of Ag NPs with smaller size and larger surface area compared to untreated silver film deposited on the untreated glass substrate. The silver-based pinhole-free SPR biosensor produced with non-perpendicular CAP treatment of both glass substrate and silver film shows E. coli detection in the distilled water in the range of 104 Colony forming unit (CFU/ml) to 108 CFU/ml with better sensitivity compared to the untreated silver-based SPR biosensor.

XPS Studies on Light-Yellow Glass Prepared by Sol-Gel Dip-Coating

2010 ◽  
Vol 177 ◽  
pp. 430-432
Author(s):  
Xin Gang Yu ◽  
Kang Yan Zeng ◽  
Shi Song Luo ◽  
Hong Wen Ma ◽  
Wen Yue Bi ◽  
...  
Keyword(s):  
Thin Film ◽  
Chemical Composition ◽  
Glass Substrate ◽  
Sol Gel ◽  
Flat Glass ◽  
Stable State ◽  
Dip Coating ◽  
Yellow Glass ◽  
Light Yellow ◽  
Silver Thin Film

Light-yellow glass was prepared by coating silver film on the flat glass substrate surface with sol-gel dip-coating process. The chemical composition and the valence state of elements on the surface of silver thin film deposited on glass substrate were studied by X-ray photoelectron spectroscopy. Results show that: elements of Na, Mg, Ca exist in the form of their respective stable state, such as Na2O, MgO, CaO, when heat treated at 500°C for 0.5h; but Si is unstable, and exhibit stoichiometrical disturbances. Results of chemical composition and their content by weight percent of silver thin film surface reveal that minute of quantity silver on the glass surface can lead to the glass with light-yellow color. The transmission of light for the light-yellow glass, deep-yellow glass and the flat glass substrate was also analyzed by spectrophotometer, and the results indicate that the light-yellow glass is capable of absorbing UV rays heavily.

Optical and Mechanical Properties of Silver Film on Glass Substrate

2010 ◽  
Vol 97-101 ◽  
pp. 1412-1415 ◽  
Author(s):  
Shiuh Chuan Her ◽  
Yi Hsia Wang
Keyword(s):  
Thin Film ◽  
Glass Substrate ◽  
Silver Film ◽  
Wavelength Region ◽  
Surface Topology ◽  
Silver Films ◽  
Atomic Force ◽  
Environmental Test ◽  
Optical And Mechanical Properties ◽  
Measured Hardness

Silver films were prepared on the glass substrate by electron-beam vapor deposition. The reflectivity of the Ag thin film was measured by a Perkin-Elmer Lambda spectrophotometer in the wavelength region of 450-680 nm. The experimental measurements of reflectivity were validated with the numerical results using the Essential Macleod software. The surface topology and microstructure of the film were examined by means of atomic force microscope (AFM). The effects of the thermal and humidity on the reflectivity of the Ag film were examined by the environmental test. Nanoindentation tests were employed to determine the hardness of the film. The measured hardness of the Ag thin film was found to depend on the penetration depth.

Preparation and Characterization of Silver Citrate Nano-Emulsion and Nano-Silver Film

2008 ◽  
Vol 373-374 ◽  
pp. 698-701
Author(s):  
Li Xin Mo ◽  
Lu Hai Li ◽  
Ya Ling Li ◽  
Zhong Xiao Li ◽  
Ming Wang
Keyword(s):  
Thin Film ◽  
Silver Film ◽  
Particle Surface ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Visible Absorption ◽  
Nano Scale ◽  
Silver Thin Film ◽  
Uv Visible ◽  
Pet Substrate

To prepare the nano-scale silver carboxylate emulsions and investigate their applications in the preparation of nano-scale silver films, the silver citrate emulsion was synthesized through the reaction of silver nitrate with sodium citrate in the presence of polyvinylpyrrolidone (PVP) as a surface modification agent in water. The emulsion was coated onto the surface of the PET substrate to form a thin latex layer of silver citrate. And this was followed by drying at about 100 °C. Then, the silver citrate thin film was deoxidized by aqueous ascorbic acid. Finally, a translucent silver thin film was formed on the surface of the PET substrate. Properties of the silver citrate emulsion and the silver film on the PET were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), laser particle size analysis, scanning electron microscopy (SEM), thermogravimetry(TG) ,UV-visible absorption spectroscopy, atomic force microscopy(AFM) and digital multimeter analysis. It was found that the silver citrate particle surface-modified by PVP has a nano-rod structure and homogeneous size distribution. The nano-rod was about 20 nm in diameter and 200 nm in length. For the UV-visible absorption spectrum of the thin film exhibited an absorption peak at 430 nm, the silver thin film prepared on the surface of the PET substrate was a typical nano-scale sliver film. Measurements of the sliver thin film at room temperature indicated that the silver film was electrically conductive, and the surface resistance was 2.42 k5/cm.

Synthesis and Antibacterial Studies of Nano Structured Ag Thin Films

2013 ◽  
Vol 678 ◽  
pp. 291-296 ◽  
Author(s):  
Chinnasamy Revathi ◽  
Krishnamoorthy Rajavel ◽  
Kugalur Shanmugam Ranjith ◽  
Ramasamy Thangavelu Rajendrakumar
Keyword(s):  
Thin Film ◽  
Silver Nanoparticles ◽  
Stainless Steel ◽  
Glass Substrate ◽  
Diffraction Method ◽  
Resistance Test ◽  
Microbial Resistance ◽  
Vis Spectroscopy ◽  
Silver Thin Film ◽  
Steel Substrates

Silver thin film of 5 nm thicknesses was evaporated on glass and stainless steel substrates and annealed at 300°C for one hour. Then these samples were characterized by using X-ray diffraction method (XRD), Scanning Electron Microscopy (SEM), UV-VIS spectroscopy, and subjected to anti-microbial resistance test. XRD analysis showed as deposited silver thin film coated on glass substrate and stainless steel substrates have amorphous nature. The annealed Ag thin film coated on glass and stainless steel substrates showed crystallinity with silver phase and their crystalline size were in the range of 30-40 nm and 17 nm respectively. SEM image indicates that formation of silver nanoparticles with spherical morphology after annealing on the glass substrate. But there is no nanoparticles formation was observed on annealed steel substrates. The anti microbial resistance test was done against E.Coli and that microbial growth was observed after 24 and 48 hrs. The results displayed a microbial resistance after 24 hrs for annealed Ag thin film coated on glass substrate due the formation of silver nanoparticles.

Stoichiometric composition of thin-film surface structures and its influence on the functional characteristics as regards gyroscopic devices

2020 ◽  
pp. 78-90
Author(s):  
M. A. Tit ◽  
S. N. Belyaev
Keyword(s):  
Thin Film ◽  
Titanium Nitride ◽  
Niobium Carbide ◽  
Structural Phase ◽  
Stoichiometric Composition ◽  
Film Surface ◽  
Surface Structures ◽  
Functional Surface ◽  
Base Surface ◽  
Thin Film Surface

This article considers the research results of the effect of stoichiometry on the properties of titanium nitride thin-film coatings of the float and electrostatic gyroscopes. It presents the results of tests of such mechanical and optical characteristics of titanium nitride thin-film structures as microhardness, resistance to wear and friction, and image contrast determined by the reflection coefficients of a titanium nitride base surface and a raster pattern formed by local laser oxidation. When making a rotor of a cryogenic gyroscope, the prospects of use and technological methods for the formation of functional surface structures of niobium carbide and nitride are considered. It is shown that during the formation of coatings of the required composition, the most important is the thermodynamic estimation of possible interactions. These interactions allow us to accomplish the structural-phase modification of the material, which is determined by the complex of possible topochemical reactions leading to the formation of compounds, including non-stoichiometric composition.

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