Design of a Reconfigurable THz Filter Based on Metamaterial Wire Resonators with Applications on Sensor Devices

A study on the design, simulation and characterization of a reconfigurable terahertz (THz) filter, composed of two frequency-selective surfaces (FSSs) with applications on sensor devices in general and highly sensitive stress sensors, is presented in this paper. Using the developed theoretical model, we found out that by careful tuning the wire parameters, it is possible to control the filter sensitivity and also the energy transmission and reflection that passes through the structure. Numerical modelling of both the mechanical and electromagnetic components (using the elasticity equation and Maxwell’s equations, respectively) has been undertaken for two types of the device assemblies based on different thermoplastic polymers transparent to the THz radiation, namely: high-density polyethylene (HDPE) and polytetrafluoroethylene (PTFE), operating in a THz window from 395 to 455 GHz. The numerical results allowed us to characterize the relation between the reflectance/transmittance and the amount of force required to obtain a specific frequency shift along that window. It was found that the device assembled with HDPE presents a more linear response and it is able to pass from a full transparency to almost full opacity using only its linear operating zone. Due to its characteristics, this THz filter might be an interesting solution not only for THz sensors based on reconfigurable filters but also for optical modulators for the THz domain.

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Synthesis and Characterization of a 6,6'-((1E,1'E)-(1,2phenylenebis(azanylylidene))bis(methanylylidene))b is(2-methoxy-3-((6-methoxybenzo[d]thiazol-2yl)diazenyl)phenol): as a highly sensitive reagent for determination cadmium(II) ion in the real samples

International Journal of Pharmaceutical Research ◽

10.31838/ijpr/2018.10.04.080 ◽

2018 ◽

Vol 10 (4) ◽

Keyword(s):

Synthesis And Characterization ◽

Real Samples ◽

The Real ◽

Highly Sensitive

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Synthesis and 31 P NMR characterization of new low toxic highly sensitive pH probes designed for in vivo acidic pH studies

Bioorganic & Medicinal Chemistry ◽

10.1016/s0968-0896(01)00414-x ◽

2002 ◽

Vol 10 (5) ◽

pp. 1451-1458 ◽

Cited By ~ 16

Author(s):

Sophie Martel ◽

Jean-Louis Clément ◽

Agnès Muller ◽

Marcel Culcasi ◽

Sylvia Pietri

Keyword(s):

Acidic Ph ◽

Highly Sensitive ◽

Nmr Characterization ◽

Low Toxic ◽

Ph Probes

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Shiga Toxin (Stx)-Binding Glycosphingolipids of Primary Human Renal Cortical Epithelial Cells (pHRCEpiCs) and Stx-Mediated Cytotoxicity

Toxins ◽

10.3390/toxins13020139 ◽

2021 ◽

Vol 13 (2) ◽

pp. 139

Author(s):

Johanna Detzner ◽

Elisabeth Krojnewski ◽

Gottfried Pohlentz ◽

Daniel Steil ◽

Hans-Ulrich Humpf ◽

...

Keyword(s):

Fatty Acid ◽

Epithelial Cells ◽

Shiga Toxin ◽

Saturated Fatty Acids ◽

Human Kidney ◽

Enterohemorrhagic Escherichia Coli ◽

Highly Sensitive ◽

Liquid Ordered ◽

Uremic Syndrome

Human kidney epithelial cells are supposed to be directly involved in the pathogenesis of the hemolytic–uremic syndrome (HUS) caused by Shiga toxin (Stx)-producing enterohemorrhagic Escherichia coli (EHEC). The characterization of the major and minor Stx-binding glycosphingolipids (GSLs) globotriaosylceramide (Gb3Cer) and globotetraosylceramide (Gb4Cer), respectively, of primary human renal cortical epithelial cells (pHRCEpiCs) revealed GSLs with Cer (d18:1, C16:0), Cer (d18:1, C22:0), and Cer (d18:1, C24:1/C24:0) as the dominant lipoforms. Using detergent-resistant membranes (DRMs) and non-DRMs, Gb3Cer and Gb4Cer prevailed in the DRM fractions, suggesting their association with microdomains in the liquid-ordered membrane phase. A preference of Gb3Cer and Gb4Cer endowed with C24:0 fatty acid accompanied by minor monounsaturated C24:1-harboring counterparts was observed in DRMs, whereas the C24:1 fatty acid increased in relation to the saturated equivalents in non-DRMs. A shift of the dominant phospholipid phosphatidylcholine with saturated fatty acids in the DRM to unsaturated species in the non-DRM fractions correlated with the GSL distribution. Cytotoxicity assays gave a moderate susceptibility of pHRCEpiCs to the Stx1a and Stx2a subtypes when compared to highly sensitive Vero-B4 cells. The results indicate that presence of Stx-binding GSLs per se and preferred occurrence in microdomains do not necessarily lead to a high cellular susceptibility towards Stx.

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Terahertz characterization of two-dimensional low-conductive layers enabled by metal gratings

Scientific Reports ◽

10.1038/s41598-021-82560-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Prashanth Gopalan ◽

Yunshan Wang ◽

Berardi Sensale-Rodriguez

Keyword(s):

Optical Transmission ◽

Terahertz Spectroscopy ◽

Design Guidelines ◽

Two Dimensional ◽

Highly Sensitive ◽

Transmission Measurements ◽

Metal Gratings ◽

Low Sensitivity ◽

Non Destructive

AbstractWhile terahertz spectroscopy can provide valuable information regarding the charge transport properties in semiconductors, its application for the characterization of low-conductive two-dimensional layers, i.e., σs < < 1 mS, remains elusive. This is primarily due to the low sensitivity of direct transmission measurements to such small sheet conductivity levels. In this work, we discuss harnessing the extraordinary optical transmission through gratings consisting of metallic stripes to characterize such low-conductive two-dimensional layers. We analyze the geometric tradeoffs in these structures and provide physical insights, ultimately leading to general design guidelines for experiments enabling non-contact, non-destructive, highly sensitive characterization of such layers.

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Highly Sensitive Optical Modulators with Distributed Bragg-Reflectors

Japanese Journal of Applied Physics ◽

10.1143/jjap.16.1389 ◽

1977 ◽

Vol 16 (8) ◽

pp. 1389-1394 ◽

Cited By ~ 1

Author(s):

Masahiro Okuda ◽

Kiyoshi Onaka ◽

Shigeharu Kita

Keyword(s):

Bragg Reflectors ◽

Distributed Bragg Reflectors ◽

Optical Modulators ◽

Highly Sensitive

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A New Ultrasensitive Bioluminescence-Based Method for Assaying Monoacylglycerol Lipase

International Journal of Molecular Sciences ◽

10.3390/ijms22116148 ◽

2021 ◽

Vol 22 (11) ◽

pp. 6148

Author(s):

Matteo Miceli ◽

Silvana Casati ◽

Pietro Allevi ◽

Silvia Berra ◽

Roberta Ottria ◽

...

Keyword(s):

Arachidonic Acid ◽

Kinetic Constants ◽

New Method ◽

Monoacylglycerol Lipase ◽

Enzymatic Cleavage ◽

Highly Sensitive ◽

Bioluminescence Assay ◽

Identification And Characterization ◽

In Cells

A novel bioluminescent Monoacylglycerol lipase (MAGL) substrate 6-O-arachidonoylluciferin, a D-luciferin derivative, was synthesized, physico-chemically characterized, and used as highly sensitive substrate for MAGL in an assay developed for this purpose. We present here a new method based on the enzymatic cleavage of arachidonic acid with luciferin release using human Monoacylglycerol lipase (hMAGL) followed by its reaction with a chimeric luciferase, PLG2, to produce bioluminescence. Enzymatic cleavage of the new substrate by MAGL was demonstrated, and kinetic constants Km and Vmax were determined. 6-O-arachidonoylluciferin has proved to be a highly sensitive substrate for MAGL. The bioluminescence assay (LOD 90 pM, LOQ 300 pM) is much more sensitive and should suffer fewer biological interferences in cells lysate applications than typical fluorometric methods. The assay was validated for the identification and characterization of MAGL modulators using the well-known MAGL inhibitor JZL184. The use of PLG2 displaying distinct bioluminescence color and kinetics may offer a highly desirable opportunity to extend the range of applications to cell-based assays.

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