Gold nanoparticle modified silicon nanowire array based sensor for low-cost, high sensitivity and selectivity detection of mercury ions

In this study, a novel and simple electrochemical glucose biosensor based on a silicon nanowire array (SNA) electrode was proposed. Metal-assisted etching (MAE) method using an AgNO3 and HF mixing solution as the etchant was employed to grow the silicon nanowire array (SNA) electrode. A thin gold shell is then sputtered over each silicon nanowire. Potassium ferricyanide, glucose oxidase (GOx), and a Nafion thin film were then sequentially coated onto the fabricated SNA for glucose detection. The processing time of the MAE and sputtering as well as the GOx concentration were optimized in terms of the redox peak currents of the SNA electrode. Compared with the corresponding plane gold electrode, the effective sensing area of the synthesized SNA electrode was measured to be 6.12 folds. Actual glucose detections demonstrated that the proposed SNA array electrode could operate in a linear range of 0.55 mM-11.02 mM and a very high sensitivity of 346 μA mM−1 cm−2. The proposed SNA electrode based glucose biosensor possesses advantages of simple fabrication process, low cost, and high sensitivity. It is feasible for future clinical applications.

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High sensitivity and selectivity vertically-oriented silicon nanowire array-based bioelectronic sensor platform

10.17077/etd.006000 ◽

2021 ◽

Author(s):

Bingtao Gao

Keyword(s):

Silicon Nanowire ◽

Nanowire Array ◽

High Sensitivity ◽

Sensor Platform ◽

Silicon Nanowire Array ◽

Sensitivity And Selectivity

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Modern nanobiotechnologies for efficient detection and remediation of mercury

Sensor Review ◽

10.1108/sr-12-2020-0290 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Mulayam Singh Gaur ◽

Rajni Yadav ◽

Mamta Kushwah ◽

Anna Nikolaevna Berlina

Keyword(s):

Heavy Metals ◽

Water Samples ◽

Low Cost ◽

High Sensitivity ◽

Environmental Water ◽

Mercury Ions ◽

Content Type ◽

Efficient Detection ◽

Sensitivity And Selectivity ◽

Selection Of

Purpose This information will be useful in the selection of materials and technology for the detection and removal of mercury ions at a low cost and with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. Design/methodology/approach Different nano- and bio-materials allowed for the development of a variety of biosensors – colorimetric, chemiluminescent, electrochemical, whole-cell and aptasensors – are described. The materials used for their development also make it possible to use them in removing heavy metals, which are toxic contaminants, from environmental water samples. Findings This review focuses on different technologies, tools and materials for mercury (heavy metals) detection and remediation to environmental samples. Originality/value This review gives up-to-date and systemic information on modern nanotechnology methods for heavy metal detection. Different recognition molecules and nanomaterials have been discussed for remediation to water samples. The present review may provide valuable information to researchers regarding novel mercury ions detection sensors and encourage them for further research/development.

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Detection of Mercury Ion with High Sensitivity and Selectivity Using a DNA/Graphene Oxide Hybrid Immobilized on Glass Slides

Biosensors ◽

10.3390/bios11090300 ◽

2021 ◽

Vol 11 (9) ◽

pp. 300

Author(s):

Li Gao ◽

Qiuxiang Lv ◽

Ni Xia ◽

Yuanwei Lin ◽

Feng Lin ◽

...

Keyword(s):

Graphene Oxide ◽

High Selectivity ◽

Limit Of Detection ◽

Low Cost ◽

High Sensitivity ◽

Mercury Ions ◽

Research Areas ◽

Glass Slides ◽

Highly Sensitive ◽

Sensitivity And Selectivity

Excessive mercury ions (Hg2+) cause great pollution to soil/water and pose a major threat to human health. The high sensitivity and high selectivity in the Hg2+ detection demonstrated herein are significant for the research areas of analytical chemistry, chemical biology, physical chemistry, drug discovery, and clinical diagnosis. In this study, a series of simple, low-cost, and highly sensitive biochips based on a graphene oxide (GO)/DNA hybrid was developed. Hg2+ is detected with high sensitivity and selectivity by GO/DNA hybrid biochips immobilized on glass slides. The performance of the biosensors can be improved by introducing more phosphorothioate sites and complementary bases. The best limit of detection of the biochips is 0.38 nM with selectivity of over 10:1. This sensor was also used for Hg2+ detection in Dendrobium. The results show this biochip is promising for Hg2+ detection.

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Reusable Surface-Enhanced Raman Spectroscopy Substrates Made of Silicon Nanowire Array Coated with Silver Nanoparticles Fabricated by Metal-Assisted Chemical Etching and Photonic Reduction

Nanomaterials ◽

10.3390/nano9111531 ◽

2019 ◽

Vol 9 (11) ◽

pp. 1531 ◽

Cited By ~ 2

Author(s):

Shi Bai ◽

Yongjun Du ◽

Chunyan Wang ◽

Jian Wu ◽

Koji Sugioka

Keyword(s):

Silver Nanoparticles ◽

Chemical Etching ◽

Silicon Nanowire ◽

Nanowire Array ◽

Surface Enhanced Raman Spectroscopy ◽

Sers Substrate ◽

Silicon Nanowire Array ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Metal Assisted Chemical Etching

Surface-enhanced Raman spectroscopy (SERS) has advanced over the last four decades and has become an attractive tool for highly sensitive analysis in fields such as medicine and environmental monitoring. Recently, there has been an urgent demand for reusable and long-lived SERS substrates as a means of reducing the costs associated with this technique To this end, we fabricated a SERS substrate comprising a silicon nanowire array coated with silver nanoparticles, using metal-assisted chemical etching followed by photonic reduction. The morphology and growth mechanism of the SERS substrate were carefully examined and the performance of the fabricated SERS substrate was tested using rhodamine 6G and dopamine hydrochloride. The data show that this new substrate provides an enhancement factor of nearly 1 × 108. This work demonstrates that a silicon nanowire array coated with silver nanoparticles is sensitive and sufficiently robust to allow repeated reuse. These results suggest that this newly developed technique could allow SERS to be used in many commercial applications.

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