scholarly journals Biomedical Sensing with Free-Standing Complementary Supercell Terahertz Metasurfaces

Crystals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 372
Author(s):  
Ibraheem Al-Naib
Keyword(s):  
Dipole Moments ◽  
Label Free ◽  
Free Standing ◽  
Biomedical Sensing ◽  
Double Stranded Dna ◽  
Scattered Fields ◽  
In Situ Detection ◽  
Index Unit ◽  
Excited Resonance

We present a free-standing terahertz metasurface supercell that consists of four complementary mirrored asymmetric split-rectangular resonators. The quality factor of the excited resonance of this supercell has been significantly improved by 250% when compared to its counterpart nonmirrored supercell. The mirroring of the resonators leads to an enhanced out-of-phase oscillating current in each neighboring resonators of the supercell. In turn, this leads to a suppression of the dipole moments and its corresponding scattered fields. Moreover, this design can be realized by utilizing a simple laser machining technique. Furthermore, we numerically evaluate the performance of this design as a label-free biosensor for thin-film analytes and biomolecules such as double-stranded DNA and single-stranded RNA viruses. A sensitivity level of 1.14 × 105 nm/refractive index unit (RIU) can be achieved using this design. Therefore, this design has the potential to be used as an effective label-free biomedical sensor for in-situ detection of various biomolecules.

Ultra-sensitive in situ detection of silver ions using a quartz crystal microbalance

2015 ◽  
Vol 39 (10) ◽  
pp. 8028-8034 ◽  
Author(s):  
Sangmyung Lee ◽  
Kuewhan Jang ◽  
Chanho Park ◽  
Juneseok You ◽  
Taegyu Kim ◽  
...  
Keyword(s):  
Drinking Water ◽  
Quartz Crystal Microbalance ◽  
Quartz Crystal ◽  
Silver Ions ◽  
Silver Ion ◽  
Label Free ◽  
Laboratory Conditions ◽  
In Situ Detection

Label-free, ultra-sensitive and in situ detection of silver ion was achieved using a quartz crystal microbalance in laboratory conditions and drinking water.

AN ELLIPSOMETRIC STUDY ON THE DENSITY AND FUNCTIONALITY OF ANTIBODY LAYERS IMMOBILIZED BY A RANDOMLY COVALENT METHOD AND A PROTEIN A-ORIENTED METHOD

2009 ◽  
Vol 21 (05) ◽  
pp. 303-310 ◽  
Author(s):  
Da-Shin Wang ◽  
Chia-Chen Chang ◽  
Shiue-Ching Shih ◽  
Chii-Wann Lin
Keyword(s):  
Protein A ◽  
Covalent Immobilization ◽  
Effective Thickness ◽  
Label Free ◽  
Ellipsometric Measurement ◽  
Antigen Capture ◽  
Ellipsometric Study ◽  
In Situ Detection ◽  
Surface Antibodies

Ellipsometry is used to quantitatively evaluate the antigen-sensing capability of immuno-surfaces. The ellipsometric measurement is a rapid, label-free, and in situ detection; however, quantification of analytes by ellipsometry is not unambiguous. The proper use of the effective thickness as a measure for the amount of analytes is addressed in this article. Taking the effective thickness as the quantification reference, we find that employing protein A to immobilize antibodies makes the antigen capture two to three times higher than the covalent immobilization technique using N-succinimidyl 4-maleimidobutyrate (GMBS). Besides, the results also suggest a uniform orientation of antibodies achieved by protein A. Increasing the density of surface antibodies would improve the sensitivity as well; however, the effect is more crucial for the protein A immuno-surface and appears to be less important for the GMBS immuno-surface. Therefore, the optimal immobilization strategy should include an orientation layer, such as protein A, and maximize the amount of oriented antibodies on the surface to further improve the efficiency for antigen detection.

Rapid quantification and in situ detection of nitrifying bacteria in biofilms by monoclonal antibody method

2000 ◽  
Vol 41 (4-5) ◽  
pp. 301-308 ◽  
Author(s):  
N. Noda ◽  
H. Ikuta ◽  
Y. Ebie ◽  
A. Hirata ◽  
S. Tsuneda ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Monoclonal Antibodies ◽  
Fluorescent Antibody ◽  
Nitrifying Bacteria ◽  
Fluorescent Antibody Technique ◽  
Antibody Technique ◽  
Antibody Method ◽  
In Situ Detection ◽  
Rapid Quantification

Fluorescent antibody technique by the monoclonal antibody method is very useful and helpful for the rapid quantification and in situ detection of the specific bacteria like nitrifiers in a mixed baxterial habitat such as a biofilm. In this study, twelve monoclonal antibodies against Nitrosomonas europaea (IFO14298) and sixteen against Nitrobacter winogradskyi (IFO14297) were raised from splenocytes of mice (BALB/c). It was found that these antibodies exhibited little cross reactivity against various kinds of heterotrophic bacteria. The direct cell count method using monoclonal antibodies could exactly detect and rapidly quantify N. europaea and N. winogradskyi. Moreover, the distribution of N. europaea and N. winogradskyi in a biofilm could be examined by in situ fluorescent antibody technique. It was shown that most of N. winogradskyi existed near the surface part and most of N. europaea existed at the inner part of the polyethylene glycol (PEG) gel pellet, which had entrapped activated sludge and used in a landfill leachate treatment reactor. It was suggested that this monoclonal antibody method was utilized for estimating and controlling the population of nitrifying bacteria as a quick and favorable tool.

scholarly journals Single Step In Situ Detection of Surface Protein and MicroRNA in Clustered Extracellular Vesicles Using Flow Cytometry

2021 ◽  
Vol 10 (2) ◽  
pp. 319
Author(s):  
Hee Cheol Yang ◽  
Won Jong Rhee
Keyword(s):  
Extracellular Vesicles ◽  
Liquid Biopsy ◽  
Molecular Beacon ◽  
Disease Diagnosis ◽  
Single Step ◽  
Flow Cytometer ◽  
Surface Proteins ◽  
Biomarker Detection ◽  
In Situ Detection

Because cancers are heterogeneous, it is evident that multiplexed detection is required to achieve disease diagnosis with high accuracy and specificity. Extracellular vesicles (EVs) have been a subject of great interest as sources of novel biomarkers for cancer liquid biopsy. However, EVs are nano-sized particles that are difficult to handle; thus, it is necessary to develop a method that enables efficient and straightforward EV biomarker detection. In the present study, we developed a method for single step in situ detection of EV surface proteins and inner miRNAs simultaneously using a flow cytometer. CD63 antibody and molecular beacon-21 were investigated for multiplexed biomarker detection in normal and cancer EVs. A phospholipid-polymer-phospholipid conjugate was introduced to induce clustering of the EVs analyzed using nanoparticle tracking analysis, which enhanced the detection signals. As a result, the method could detect and distinguish cancer cell-derived EVs using a flow cytometer. Thus, single step in situ detection of multiple EV biomarkers using a flow cytometer can be applied as a simple, labor- and time-saving, non-invasive liquid biopsy for the diagnosis of various diseases, including cancer.

In Situ Detection of Local Structure Transformation of 2D SnSe Nanosheets through Nanothermomechanical Behavior

2021 ◽  
pp. 2100121
Author(s):  
Zhibin Liu ◽  
Kunqi Xu ◽  
Huarong Zeng ◽  
Zhifu Liu ◽  
Kunyu Zhao ◽  
...  
Keyword(s):  
Local Structure ◽  
Structure Transformation ◽  
In Situ Detection
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