Sensitive Detection of SARS-CoV-2 Using a Novel Plasmonic Fiber Optic Biosensor Design

Abstract The coronavirus (COVID-19) pandemic has put the entire world at risk and caused an economic downturn in most countries. This work provided theoretical insight into a novel fiber optic based plasmonic biosensor that can be used for sensitive detection of SARS-CoV-2. The aim was always to achieve reliable, sensitive and reproducible detection. The proposed configuration is based on Ag–Au alloy nanoparticles films covered with a layer of graphene which promotes the molecular adsorption and a thiol-tethered DNA layer as a ligand. Here the combination of two recent approaches in a single configuration is very promising and can only lead to considerable improvement. We have theoretically analyzed the sensor performance in terms of sensitivity and resolution. To highlight the importance of the new configuration, a comparison was made with two other sensors. One is based on gold nanoparticles incorporated into a host medium, the other is composed of a bimetallic Ag-Au layer in the massive state. The numerical results obtained has been validated and show that the proposed configuration offers better sensitivity (7100 nm\RIU) and good resolution (figure of merit; FOM=38.88Tand signal-to-noise ratio; SNR=0.388). In addition, a parametric study was performed such as the graphene layers number and the size of the nanoparticles.

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Theoretical insight into the CdS/FAPbI3 heterostructure: a promising visible-light absorber

New Journal of Chemistry ◽

10.1039/d0nj04827e ◽

2021 ◽

Author(s):

Junli Chang ◽

Liping Jiang ◽

Guangzhao Wang ◽

Yuhong Huang ◽

Hong Chen

Keyword(s):

Optical Absorption ◽

Visible Light ◽

Visible Light Range ◽

Light Absorber ◽

Absorption Performance ◽

Theoretical Insight ◽

Insight Into

The optical absorption performance of the perovskite FAPbI3 in the visible-light range is significantly improved by constructing a CdS/FAPbI3 heterostructure.

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Theoretical Insight into the Reversal of Chemoselectivity in Diels-Alder Reactions of α,β-Unsaturated Aldehydes and Ketones Catalyzed by Brønsted and Lewis Acids

Organics ◽

10.3390/org2010004 ◽

2021 ◽

Vol 2 (1) ◽

pp. 38-49

Author(s):

Lakhdar Benhamed ◽

Sidi Mohamed Mekelleche ◽

Wafaa Benchouk

Keyword(s):

Lewis Acids ◽

Major Product ◽

Diels Alder ◽

Unsaturated Ketone ◽

Unsaturated Aldehydes ◽

Aldehydes And Ketones ◽

Theoretical Insight ◽

Insight Into ◽

Good Agreement

Experimentally, a reversal of chemoselectivity has been observed in catalyzed Diels–Alder reactions of α,β-unsaturated aldehydes (e.g., (2E)-but-2-enal) and ketones (e.g., 2-hexen-4-one) with cyclopentadiene. Indeed, using the triflimidic Brønsted acid Tf2NH as catalyst, the reaction gave a Diels–Alder adduct derived from α,β-unsaturated ketone as a major product. On the other hand, the use of tris(pentafluorophenyl)borane B(C6F5)3 bulky Lewis acid as catalyst gave mainly the cycloadduct of α,β-unsaturated aldehyde as a major product. Our aim in the present work is to put in evidence the role of the catalyst in the reversal of the chemoselectivity of the catalyzed Diels–Alder reactions of (2E)-but-2-enal and 2-Hexen-4-one with cyclopentadiene. The calculations were performed at the ωB97XD/6-311G(d,p) level of theory and the solvent effects of dichloromethane were taken into account using the PCM solvation model. The obtained results are in good agreement with experimental outcomes.

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Theoretical Insight into the Library Screening Approach for Binding of Intermolecular G-Quadruplex RNA and Small Molecules through Docking and Molecular Dynamics Simulation Studies

The Journal of Physical Chemistry B ◽

10.1021/acs.jpcb.0c10991 ◽

2021 ◽

Author(s):

Soma Roy ◽

Asfa Ali ◽

Santanu Bhattacharya

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Small Molecules ◽

Dynamics Simulation ◽

Library Screening ◽

Simulation Studies ◽

Screening Approach ◽

G Quadruplex ◽

Theoretical Insight ◽

Insight Into

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Theoretical insight into electronic and optical behaviour of H-adsorbed Zn-terminated Zn3N2-(100)-non-polar surface

Vacuum ◽

10.1016/j.vacuum.2021.110467 ◽

2021 ◽

pp. 110467

Author(s):

M. Kaur ◽

K. Kabra ◽

M. Rérat ◽

G. Sharma

Keyword(s):

Optical Behaviour ◽

Polar Surface ◽

Theoretical Insight ◽

Insight Into

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What makes court-referred mediation effective?

International Journal of Conflict Management ◽

10.1108/ijcma-09-2012-0071 ◽

2014 ◽

Vol 25 (1) ◽

pp. 21-37 ◽

Cited By ~ 2

Author(s):

Amira Galin

Keyword(s):

Design Methodology ◽

Content Type ◽

Process And Outcome ◽

Refusal To Participate ◽

The Impact ◽

Practical Implications ◽

Theoretical Insight ◽

Insight Into ◽

Low Rate

Purpose – The purpose of this paper is to obtain insight into court-referred mediation in the Israeli Labor Courts, by analyzing its processes and outcomes, as a function of tactics used by both the disputants and the mediator. Design/methodology/approach – Observation of 103 court-referred mediations, for each of which a detailed process and outcome were documented. Data on disputants' refusal to participate in the mediation was also collected. At the end of each mediation case, disputants were given a questionnaire in which they expressed their satisfaction with the outcome and their evaluation of the mediator's contribution. Findings – A low rate of refusal to participate in court-referred mediation was found. Also, the higher the ratio of soft tactics to pressure tactics employed (by all parties involved) during the process, the higher the rate of agreements. Mediators use significantly more soft tactics than disputants, and are more active in using tactics. The two significant variables that predict the mediation's agreement are the ratio between soft tactics to pressure tactics used by all parties, and mediator contribution to the process. Practical implications – The significant role of soft tactics in the process, outcome, and satisfaction of court-referred mediation may serve as a guideline for disputants and mediators. Originality/value – This unique research, which examines the impact of tactics on court-referred mediation, may provide added and significant theoretical insight into its process and outcome, as well as a better understanding of other “hybrid” (compulsory at the beginning, voluntary at the end) mediations.

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