Direct electrochemical bacterial sensor using ZnO nanorods disposable electrode

Sensor Review ◽  
2018 ◽  
Vol 38 (3) ◽  
pp. 326-334 ◽  
Author(s):  
Mohamed Ghazi Al-Fandi ◽  
Nid’a Hamdan Alshraiedeh ◽  
Rami Joseph Oweis ◽  
Rawan Hassan Hayajneh ◽  
Iman Riyad Alhamdan ◽  
...  

Purpose This paper aims to report a prototype of a reliable method for rapid, sensitive bacterial detection by using a low-cost zinc oxide nanorods (ZnONRs)-based electrochemical sensor. Design/methodology/approach The ZnONRs have been grown on the surface of a disposable, miniaturized working electrode (WE) using the low-temperature hydrothermal technique. Scanning electron microscopy and energy dispersion spectroscopy have been performed to characterize the distribution as well as the chemical composition of the ZnONRs on the surface, respectively. Moreover, the cyclic voltammetry test has been implemented to assess the effect of the ZnONRs on the signal conductivity between −1 V and 1 V with a scan rate of 0.01 V/s. Likewise, the effect of using different bacterial concentrations in phosphate-buffered saline has been investigated. Findings The morphological characterization has shown a highly distributed ZnONR on the WE with uneven alignment. Also, the achieved response time was about 12 minutes and the lower limit of detection was approximately 103 CFU abbreviation for Colony Forming Unit/mL. Originality/value This paper illustrates an outcome of an experimental work on a ZnONRs-based electrochemical biosensor for direct detection of bacteria.

2021 ◽  
Vol 19 (48) ◽  
pp. 66-78
Author(s):  
Lina Zeki Yahiya ◽  
Mohamed K. Dhahir

The preparation and characterization of innovative nanocomposites based on zinc oxide nanorods (ZNR) encapsulated by graphene (Gr) nanosheets and decorated with silver (Ag), and cupper (Cu) nanoparticles (NP) were studied. The prepared nanocomposites (ZNR@Gr/Cu-Ag) were examined by different techniques including Field Emission Scanning Electron Microscope (FESEM), Transmission electron microscopy (TEM), Atomic force microscopy (AFM), UV-Vis spectrophotometer and fluorescence spectroscopy. The results showed that the ZNR has been good cover by five layers of graphene and decorated with Ag and Cu NPs with particles size of about 10-15 nm. The ZNR@Gr/Cu-Ag nanocomposites exhibit high absorption behavior in ultraviolet (UV) region of spectrum. In comparison with ZNR, the ZNR@Gr/Cu-Ag nanocomposites reveal superior absorption in the entire region of 387–1000 nm. Moreover, the band gap decreases from 3.2 eV of ZNR to 1.2 eV for ZNR@Gr/Cu-Ag nanocomposites. Taking into account the superiority of ZNR@Gr/Cu-Ag nanocomposites in terms of easy fabrication, low cost method, and environmental friendliness which made it favorable for huge-scale preparation in many applications such as water splitting, sensor, solar cell, antibacterial and optoelectronic devices.


Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 1004 ◽  
Author(s):  
Zouhair Ait-Touchente ◽  
Houssem Eddine El Yamine Sakhraoui ◽  
Najla Fourati ◽  
Chouki Zerrouki ◽  
Naima Maouche ◽  
...  

This study concerns the design of an ion-imprinted polymer (IIP) for the selective detection of mercury II ions. Compared to other electrochemical studies, the originality of this work lies to the fact that the IIP was electropolymerized on ZnO nanorods, which were themselves grown on gold/diazonium modified substrates. This strategy of diazonium salt and ZnO nanorods permits to increase considerably the specific surface and thus to improve the sensor’s performances. The limit of detection (LOD) of the designed sensor was of order of 1 pM, the lowest value ever reported in literature.


2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Arun Vasudevan ◽  
Soyoun Jung ◽  
Taeksoo Ji

We present ZnO nanorods grown by a low-cost hydrolysis method with a rod diameter on the order of 30–40 nm and spacing on the order of 20–40 nm that find their applications in the field of solar cells and UV photodetectors with high efficiency and sensitivity. The effect of different process parameters on nanorod growth, such as the seed layer orientation in the growth medium, and the concentration of the growth medium were studied while characterizing the structure of the grown nanorods using XRD, EDAX, and SEM.


2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Anh Thi Le ◽  
Swee-Yong Pung

Purpose This paper aims to investigate the reusability of metal/metal oxide-coupled ZnO nanorods (ZnO NRs) to degrade rhodamine B (RhB). Design/methodology/approach ZnO NRs particles were synthesized by precipitation method and used to remove various types of metal ions such as Cu2+, Ag+, Mn2+, Ni2+, Pb2+, Cd2+ and Cr2+ ions under UV illumination. The metal/metal oxide-coupled ZnO NRs were characterized by scanning electron microscope, X-ray diffraction and UV-Vis diffuse reflectance. The photodegradation of RhB dye by these metal/metal oxide-coupled ZnO NRs under UV exposure was assessed. Findings The metal/metal oxide-coupled ZnO NRs were successfully reused to remove RhB dye in which more than >90% of RhB dye was degraded under UV exposure. Furthermore, the coupling of Ag, CuO, MnO2, Cd and Ni particles onto the surface of ZnO NRs even enhanced the degradation of dye. The dominant reactive species involved in the degradation of RhB dye were •OH- and •O2−-free radicals. Research limitations/implications The coupling of metal/metal oxide onto the surface of ZnO NRs after metal ions removal could affect the photocatalytic performance of ZnO NRs in the degradation of organic pollutants in subsequent stage. Practical implications A good reusability performance of metal/metal oxide-coupled ZnO NRs make ZnO NRs become a desirable photocatalyst material for the treatment of wastewater, which consists of both heavy metal ions and organic dyes. Originality/value Metal/metal oxide coupling onto the surface of ZnO NRs particles improved subsequent UV-assisted photocatalytic degradation of RhB dye.


2008 ◽  
Vol 8 (11) ◽  
pp. 5854-5857 ◽  
Author(s):  
Guangping Zhu ◽  
Chunxiang Xu ◽  
Jing Zhu ◽  
Changgui Lu ◽  
Yiping Cui ◽  
...  

High density zinc oxide nanorods with uniform size were synthesized on (100) silicon substrate by vapor-phase transport method. The scanning electron microscopy images reveal that the nanorods have an average diameter of about 400 nm. The X-ray diffraction pattern demonstrates the wurtzite crystalline structure of the ZnO nanorods growing along [0001] direction. The single-photon excited photoluminescence presents a strong ultraviolet emission band at 394 nm and a weak visible emission band at 600 nm. When the ZnO nanorods were respectively pumped by various wavelength lasers from 520 nm to 700 nm, two-photon excited ultraviolet photoluminescence was observed. The dependence of the two-photon excited photoluminescence intensity on the excitation wavelength and power was investigated in detail.


2011 ◽  
Vol 10 (04n05) ◽  
pp. 845-849
Author(s):  
GAURAV SHUKLA ◽  
ALIKA KHARE

Hydrothermal growth of highly c-axis oriented ZnO nanorods with high aspect ratio on pulsed laser deposited ZnO seed layer is reported. Effect of pre-heating time, growth time and seed layer on the structural, morphological and optical properties of ZnO nanorods is presented. The possible growth mechanism for ZnO nanorods is also discussed.


2011 ◽  
Vol 78 (6) ◽  
pp. 1930-1935 ◽  
Author(s):  
Suzanne L. Hennigan ◽  
Jeremy D. Driskell ◽  
Naola Ferguson-Noel ◽  
Richard A. Dluhy ◽  
Yiping Zhao ◽  
...  

ABSTRACTMycoplasma gallisepticumis a bacterial pathogen of poultry that is estimated to cause annual losses exceeding $780 million. The National Poultry Improvement Plan guidelines recommend regular surveillance and intervention strategies to containM. gallisepticuminfections and ensure mycoplasma-free avian stocks, but several factors make detection ofM. gallisepticumand diagnosis ofM. gallisepticuminfection a major challenge. Current techniques are laborious, require special expertise, and are typically plagued by false results. In this study, we describe a novel detection strategy which uses silver nanorod array–surface-enhanced Raman spectroscopy (NA-SERS) for direct detection of avian mycoplasmas. As a proof of concept for use in avian diagnostics, we used NA-SERS to detect and differentiate multiple strains of avian mycoplasma species, includingAcholeplasma laidlawii,Mycoplasma gallinarum,Mycoplasma gallinaceum,Mycoplasma synoviae, andM. gallisepticum, including vaccine strains 6/85, F, and ts-11. Chemometric multivariate analysis of spectral data was used to classify these species rapidly and accurately, with >93% sensitivity and specificity. Furthermore, NA-SERS had a lower limit of detection that was 100-fold greater than that of standard PCR and comparable to that of real-time quantitative PCR. Detection ofM. gallisepticumin choanal cleft swabs from experimentally infected birds yielded good sensitivity and specificity, suggesting that NA-SERS is applicable for clinical detection.


2013 ◽  
Vol 26 ◽  
pp. 33-38 ◽  
Author(s):  
Ruziana Mohamed ◽  
Zuraida Khusaimi ◽  
A.N. Afaah ◽  
Aadila Aziz ◽  
Mohamad Hafiz Mamat ◽  
...  

Magnesium (Mg)-doped zinc oxides (ZnO) have been prepared on a silicon substrate by using the solution-immersion method. The nanorods films were annealed at different temperature 0°C, 250°C, 500°C respectively for 1 hour. The XRD diffraction indicated that the Mg-doped ZnO nanorods have good crystallinity with a hexagonal wurzite structure preferentially oriented along the (002) direction. PL spectroscopy at room temperature shows strong UV peaks appearing at 383 nm when annealed at 250°C. The intensity of broad emission peaks increases with increasing annealing temperature to 500°C which is possibility attributed to intrinsic defects.


Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 922 ◽  
Author(s):  
Francesca Luzi ◽  
Alessandro Di Michele ◽  
Luigi Torre ◽  
Debora Puglia

Poly(vinyl alcohol-co-ethylene) (EVOH) films containing zinc oxide nanorods (ZnO Nrods) at 0.1, 0.5, and 1 wt%, were realized by solvent casting. The effect of ZnO Nrods content on morphological, thermal, optical, mechanical, and oxygen permeability properties were analyzed. In addition, moisture content and accelerated-aging test studies were performed, with the intention to determine the influence of zinc oxide nanofillers on the functional characteristics of realized packaging systems. Tensile properties showed increased values for strength and deformation-at-break in EVOH-based formulations reinforced with 0.1 and 0.5 wt% of zinc oxide nanorods. Results from the colorimetric and transparency investigations underlined that the presence of ZnO Nrods in EVOH copolymer did not induce evident alterations. In addition, after the accelerated-aging test, the colorimetric test confirmed the possibility for these materials to be used in the packaging sector. This behavior was induced by the presence of zinc oxide nanofillers that act as a UV block that made them useful as an efficient absorber of UV radiation.


Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3168 ◽  
Author(s):  
Alexander Tamashevski ◽  
Yuliya Harmaza ◽  
Ekaterina Slobozhanina ◽  
Roman Viter ◽  
Igor Iatsunskyi

The precise detection of cancer cells currently remains a global challenge. One-dimensional (1D) semiconductor nanostructures (e.g., ZnO nanorods) have attracted attention due to their potential use in cancer biosensors. In the current study, it was demonstrated that the possibility of a photoluminescent detection of human leukemic T-cells by using a zinc oxide nanorods (ZnO NRs) platform. Monoclonal antibodies (MABs) anti-CD5 against a cluster of differentiation (CD) proteins on the pathologic cell surface have been used as a bioselective layer on the ZnO surface. The optimal concentration of the protein anti-CD5 to form an effective bioselective layer on the ZnO NRs surface was selected. The novel biosensing platforms based on glass/ZnO NRs/anti-CD5 were tested towards the human T-lymphoblast cell line MOLT-4 derived from patients with acute lymphoblastic leukemia. The control tests towards MOLT-4 cells were performed by using the glass/ZnO NRs/anti-IgG2a system as a negative control. It was shown that the photoluminescence signal of the glass/ZnO NRs/anti-CD5 system increased after adsorption of T-lymphoblast MOLT-4 cells on the biosensor surface. The increase in the ZnO NRs photoluminescence intensity correlated with the number of CD5-positive MOLT-4 cells in the investigated population (controlled by using flow cytometry). Perspectives of the developed ZnO platforms as an efficient cancer cell biosensor were discussed.


Sign in / Sign up

Export Citation Format

Share Document