Localized Collection of Airborne Analytes: A Transport Driven Approach to Improve the Response Time of Existing Gas Sensor Designs including SERS based Detection of Small Molecules

ABSTRACTThe detection of single molecular binding events has been a recent trend in sensor research introducing various sensor designs where the active sensing elements are nanoscopic in size. Currently, diffusion-only-transport is often used and it becomes increasingly unlikely for an analyte molecule to “find” and interact with sensing structures where the active area is shrunk in size, trading an increased sensitivity with a long response time. This report introduces electrodynamic nanolens based analyte concentration concepts to transport airborne analytes to nanoscopic sensing points to improve the response time of existing gas sensor designs. In all cases we find that the collection rate is several orders of magnitudes higher than in the case where the collection is driven by diffusion.

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Increased sensitivity of a gas sensor by controlled extension of TiO2 active area

10.1063/1.5048884 ◽

2018 ◽

Cited By ~ 1

Author(s):

Pavol Nemec ◽

Ivan Hotový ◽

Robert Andok ◽

Ivan Kostič

Keyword(s):

Gas Sensor ◽

Active Area ◽

Increased Sensitivity

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Ammonia Gas Sensing Characteristic of P3HT-rGO-MWCNT Composite Films

Applied Sciences ◽

10.3390/app11156675 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6675

Author(s):

Tran Si Trong Khanh ◽

Tran Quang Trung ◽

Le Thuy Thanh Giang ◽

Tran Quang Nguyen ◽

Nguyen Dinh Lam ◽

...

Keyword(s):

Response Time ◽

Gas Sensor ◽

Gas Sensing ◽

Composite Films ◽

Weight Ratio ◽

Film Surface ◽

Relative Sensitivity ◽

Ammonia Gas ◽

Casting Technique ◽

Multi Walled Carbon Nanotubes

In this work, the P3HT:rGO:MWCNTs (PGC) nanocomposite film applied to the ammonia gas sensor was successfully fabricated by a drop-casting technique. The results demonstrated that the optimum weight ratio of the PGC nanocomposite gas sensor is 20%:60%:20% as the weight ratio of P3HT:rGO:MWCNTs (called PGC-60). This weight ratio leads to the formation of nanostructured composites, causing the efficient adsorption/desorption of ammonia gas in/out of the film surface. The sensor based on PGC-60 possessed a response time of 30 s, sensitivity up to 3.6% at ammonia gas concentration of 10 ppm, and relative sensitivity of 0.031%/ppm. These results could be attributed to excellent electron transportation of rGO, the main adsorption activator to NH3 gas of P3HT, and holes move from P3HT to the cathodes, which works as charge “nano-bridges” carriers of Multi-Walled Carbon Nanotubes (MWCNTs). In general, these three components of PGC sensors have significantly contributed to the improvement of both the sensitivity and response time in the NH3 gas sensor.

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Metabolomics in nutrition research–a powerful window into nutritional metabolism

Essays in Biochemistry ◽

10.1042/ebc20160029 ◽

2016 ◽

Vol 60 (5) ◽

pp. 451-458 ◽

Cited By ~ 13

Author(s):

Lorraine Brennan

Keyword(s):

Mass Spectrometry ◽

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Data Acquisition ◽

Small Molecules ◽

Biological Samples ◽

Metabolic Pathways ◽

Recent Trend ◽

Disease States ◽

Nutrition Research

Metabolomics is the study of small molecules present in biological samples. In recent years it has become evident that such small molecules, called metabolites, play a key role in the development of disease states. Furthermore, metabolomic applications can reveal information about alterations in certain metabolic pathways under different conditions. Data acquisition in metabolomics is usually performed using nuclear magnetic resonance (NMR)-based approaches or mass spectrometry (MS)-based approaches with a more recent trend including the application of multiple platforms in order to maximise the coverage in terms of metabolites measured. The application of metabolomics is rapidly increasing and the present review will highlight applications in nutrition research.

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Influence of doping on sensitivity and response time of TiO2 oxygen gas sensor

Review of Scientific Instruments ◽

10.1063/1.1150487 ◽

2000 ◽

Vol 71 (3) ◽

pp. 1500-1504 ◽

Cited By ~ 9

Author(s):

Rajnish K. Sharma ◽

M. C. Bhatnagar ◽

G. L. Sharma

Keyword(s):

Response Time ◽

Gas Sensor ◽

Oxygen Gas

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A novel gas sensor based on porous α-Ni(OH)2 ultrathin nanosheet/reduced graphene oxide composites for room temperature detection of NOx

New Journal of Chemistry ◽

10.1039/c5nj03284a ◽

2016 ◽

Vol 40 (5) ◽

pp. 4678-4686 ◽

Cited By ~ 11

Author(s):

Ying Yang ◽

Hongjie Wang ◽

Linlin Wang ◽

Yunlong Ge ◽

Kan Kan ◽

...

Keyword(s):

Graphene Oxide ◽

Response Time ◽

Reduced Graphene Oxide ◽

Gas Sensor ◽

Room Temperature ◽

Temperature Detection ◽

Reduced Graphene ◽

Ultrathin Nanosheet ◽

Oxide Composites

Porous α-Ni(OH)2 TNS/rGO composites have a sensitivity of 64.4% and a response time of 10.0 s to 97.0 ppm NOx.

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Possible Anti-viral effects of Neem (Azadirachta indica) on Dengue virus

10.1101/2020.04.29.069567 ◽

2020 ◽

Author(s):

Vikas B Rao ◽

Kalidas Yeturu

Keyword(s):

Dengue Virus ◽

Small Molecules ◽

Azadirachta Indica ◽

Antiviral Drug ◽

Experimental Studies ◽

Major Health ◽

Molecular Binding ◽

Scientific Curiosity ◽

Mosquito Breeding ◽

Health Complications

Dengue virus (DENV) has become a major health threat worldwide accounting for 50-100 million infections every year and keeping 2.5 billion people at a risk of the infection. Seriousness of the viral infection can be attributed to its lethality when not treated in time and potential to cause health complications post infection. Currently there are only preventive strategies and development of vaccination is still in its infancy of research. It is therefore highly necessary to discover newer drugs and therapies for this deadly virus. In this paper we report important insights we have obtained through a computational analysis of small molecules of Neem (Azadirachta indica) against dengue viral proteins and its required proteins in human. Our study involves identification of the effect of specific small molecules of Neem on proteins of human and virus corresponding to different pathways using simulated molecular binding analyses. We report here Gedunin and Pongamol contained in naturally occurring Neem as potential drugs against the Dengue virus.Significance StatementWe report important ligands in Neem that have potential antiviral activity against Dengue. Our selection of Neem for testing for antiviral properties has been inspired from Ayurveda. Due to unhygienic living conditions that facilitate mosquito breeding, Dengue is a major threat in developing countries causing millions of deaths. Despite the severity of the infection, no specific antiviral drug is available. The results obtained, in terms of newer potential ligands against Dengue are significant as this provides a basis for experimentally verifying and extending the same to develop a cure.We hope that this study would would spur scientific curiosity and undertaking of further elaborate experimental studies.

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