Label-Free Detection of a Biomarker with Piezoelectric Micro Cantilever Based on Mass Micro Balancing

With a piezoelectric micro cantilever sensor, a biomarker for various cancers is detected up to the concentration level required to determine a disease by using the mass micro balancing whose principle is that change of mechanical vibrant frequency is measured due to a target material attached on a sensor structure. The used piezoelectric micro cantilever sensor is designed so as to have the sufficient values of mass sensitivity and reliability. The used piezoelectric film, which acts as both sensor and actuator, is a plumbum zirconate titanate (PZT). Geometrical dimension of the micro cantilever is 100 μm (length) by 30 μm (width) by 5 μm (thickness). The 50-μm-long PZT film with thickness of 2.5 μm is covered from its root to its middle. Carcinoembryonic antigen (CEA), the biomarker for testing the sensor as label-free detection for pathological tests, is known as a biomarker for various cancers. The critical value of CEA concentration is known as 30 pM (5 ng/mL), and it is detected by the binding of antigen and antibody from high concentration to the critical concentration. From the results, the sensor could be applied to label-free detection sensors for pathological tests.

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Finite Element Method-based Design and Simulations of Micro-cantilever Platform for Chemical and Bio-sensing Applications

Defence Science Journal ◽

10.14429/dsj.66.10702 ◽

2016 ◽

Vol 66 (5) ◽

pp. 485 ◽

Cited By ~ 1

Author(s):

R. Agarwal ◽

R. Mukhiya ◽

R. Sharma ◽

M.K. Sharma ◽

A.K. Goel

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Label Free ◽

Device Structure ◽

Micro Electro Mechanical Systems ◽

Sensing Applications ◽

Toxic Agents ◽

Label Free Detection ◽

Micro Cantilever ◽

Element Method

Micro-electro-mechanical systems (MEMS)-based cantilever platform have capability for the detection of chemical and biological agents. This paper reports about the finite element method (FEM) based design and simulations of MEMS-based piezoresistor cantilever platform to be used for detection of chemical and biological toxic agents. Bulk micromachining technique is adopted for the realisation of the device structure. MEMS piezoresistive biosensing platforms are having potential for a field-based label-free detection of various types of bio-molecules. Using the MEMMECH module of CoventorWare® simulations are performed on the designed model of the device and it is observed that principal stress is maximum along the length (among other dimensions of the micro-cantilever) and remains almost constant for 90 per cent of the length of the micro-cantilever. The dimensions of piezoresistor are optimised and the output voltage vs. stress analysis for various lengths of the piezoresistor is performed using the MEMPZR module of the CoventorWare®.

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Label-Free Detection of Ovarian Cancer Antigen CA125 by Surface Enhanced Raman Scattering

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17141 ◽

2020 ◽

Vol 20 (3) ◽

pp. 1358-1365 ◽

Cited By ~ 1

Author(s):

İlknur TunÇ ◽

Hepi Hari Susapto

Keyword(s):

Raman Spectroscopy ◽

Organic Molecules ◽

Concentration Level ◽

Hot Spot ◽

Surface Enhanced Raman Spectroscopy ◽

Label Free ◽

Time Resolved ◽

Label Free Detection ◽

Surface Enhanced ◽

Surface Enhanced Raman

Surface-enhanced Raman spectroscopy (SERS) has drawn attention in recent years for imaging biologicalmolecules as an analytical tool due to its label-free approach. The SERS approach can be used in tracking organic molecules and monitoring unique Raman spectra of the organic molecules bound to metal nanoparticles (NPs). In this paper, the molecular specifity of Raman Spectroscopy was used together with self-assembled monolayer of metallic AuNPs as a sensor platform in order to detect CA125 antibody-antigen probe molecules. Highly enhanced electromagnetic fields localized around neighboring AuNPs provide hot-spot construction due to the spatial distribution of SERS enhancement on the CA125 proteins at nM concentration level. Time resolved SERS mapping of CA125 antibody and antigen couples was recorded. Even though blinking behavior was observed for some cases, vast variety SERS signals from CA125 proteins were highly reproducible. Blinking behavior is attributed to single molecular detection. Distinguished feature of SERS mapping images of CA125 antibody and antigen with such a low concentration level is very promising for this technique to be used for diagnostic purposes.

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A micro-cantilever sensor chip based on contact angle analysis for a label-free troponin I immunoassay

Lab on a Chip ◽

10.1039/c2lc40767a ◽

2013 ◽

Vol 13 (5) ◽

pp. 834 ◽

Cited By ~ 15

Author(s):

Tsung-I Yin ◽

Yunpeng Zhao ◽

Josef Horak ◽

Huseyin Bakirci ◽

Hsin-Hao Liao ◽

...

Keyword(s):

Contact Angle ◽

Troponin I ◽

Sensor Chip ◽

Label Free ◽

Cantilever Sensor ◽

Micro Cantilever ◽

Contact Angle Analysis

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Faculty Opinions recommendation of In vivo capture and label-free detection of early metastatic cells.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.725774602.793510350 ◽

2015 ◽

Author(s):

Martin Gruebele ◽

Max Platkov

Keyword(s):

Label Free ◽

Metastatic Cells ◽

Label Free Detection

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The Role of Surface Chemistry in the Efficacy of Protein and DNA Microarrays for Label-Free Detection: An Overview

Polymers ◽

10.3390/polym13071026 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1026

Author(s):

Elisa Chiodi ◽

Allison M. Marn ◽

Matthew T. Geib ◽

M. Selim Ünlü

Keyword(s):

Surface Chemistry ◽

Surface Functionalization ◽

Dna Microarrays ◽

Label Free ◽

Polymeric Coatings ◽

Label Free Detection ◽

Particle Imaging ◽

Single Particle Imaging ◽

The Impact

The importance of microarrays in diagnostics and medicine has drastically increased in the last few years. Nevertheless, the efficiency of a microarray-based assay intrinsically depends on the density and functionality of the biorecognition elements immobilized onto each sensor spot. Recently, researchers have put effort into developing new functionalization strategies and technologies which provide efficient immobilization and stability of any sort of molecule. Here, we present an overview of the most widely used methods of surface functionalization of microarray substrates, as well as the most recent advances in the field, and compare their performance in terms of optimal immobilization of the bioreceptor molecules. We focus on label-free microarrays and, in particular, we aim to describe the impact of surface chemistry on two types of microarray-based sensors: microarrays for single particle imaging and for label-free measurements of binding kinetics. Both protein and DNA microarrays are taken into consideration, and the effect of different polymeric coatings on the molecules’ functionalities is critically analyzed.

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Real-time label-free detection of DNA hybridization using a functionalized graphene field effect transistor: a theoretical study

Journal of Nanoparticle Research ◽

10.1007/s11051-021-05295-1 ◽

2021 ◽

Vol 23 (8) ◽

Author(s):

Sheida Bagherzadeh-Nobari ◽

Reza Kalantarinejad

Keyword(s):

Real Time ◽

Dna Hybridization ◽

Field Effect ◽

Field Effect Transistor ◽

Theoretical Study ◽

Functionalized Graphene ◽

Label Free ◽

Graphene Field Effect Transistor ◽

Label Free Detection ◽

Effect Transistor

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Label-Free Electrochemical Sensor for Rapid Bacterial Pathogen Detection Using Vancomycin-Modified Highly Branched Polymers

Sensors ◽

10.3390/s21051872 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1872

Author(s):

Holger Schulze ◽

Harry Wilson ◽

Ines Cara ◽

Steven Carter ◽

Edward N. Dyson ◽

...

Keyword(s):

Pathogen Detection ◽

Electrochemical Impedance ◽

Point Of Care ◽

Branched Polymers ◽

Label Free ◽

Conformation Change ◽

Gram Positive ◽

Gram Positive Bacteria ◽

Staphylococcus Carnosus ◽

Label Free Detection

Rapid point of care tests for bacterial infection diagnosis are of great importance to reduce the misuse of antibiotics and burden of antimicrobial resistance. Here, we have successfully combined a new class of non-biological binder molecules with electrochemical impedance spectroscopy (EIS)-based sensor detection for direct, label-free detection of Gram-positive bacteria making use of the specific coil-to-globule conformation change of the vancomycin-modified highly branched polymers immobilized on the surface of gold screen-printed electrodes upon binding to Gram-positive bacteria. Staphylococcus carnosus was detected after just 20 min incubation of the sample solution with the polymer-functionalized electrodes. The polymer conformation change was quantified with two simple 1 min EIS tests before and after incubation with the sample. Tests revealed a concentration dependent signal change within an OD600 range of Staphylococcus carnosus from 0.002 to 0.1 and a clear discrimination between Gram-positive Staphylococcus carnosus and Gram-negative Escherichia coli bacteria. This exhibits a clear advancement in terms of simplified test complexity compared to existing bacteria detection tests. In addition, the polymer-functionalized electrodes showed good storage and operational stability.

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