LABEL-FREE BIOMOLECULAR DETECTION USING CARBON NANOTUBE FIELD EFFECT TRANSISTORS

Carbon nanotube field effect transistor (FET) type biosensors have been widely investigated as one of the promising platforms for highly sensitive personalized disease-monitoring electronic devices. Combined with high level cutting edge information technology (IT) infra systems, carbon nanotube transistor biosensors afford a great opportunity to contribute to human disease care by providing early diagnostic capability. Several key prerequisites that should be clarified for the real application include sensitivity, reliability, reproducibility, and expandability to multiplex detection systems. In this brief review, we introduce the types, fabrication, and detection methods of single-walled carbon nanotube FET (SWNT-FET) devices. As surface functionalization of the devices by which nonspecific bindings (NSBs) are efficiently prohibited is also another important issue regarding reliable biosensors, we discuss several key strategies about surface passivation along with examples of various biomolecules such as proteins, DNA, small molecules, aptamers, viruses, and cancer and neurodegenerative disease markers which have been successfully sensed by SWNT-FET devices. Finally, we discuss proposed detection mechanisms, according to which strategies for fabricating sensor devices having high sensitivity are determined. Two main mechanisms — charge transfer (or electrostatic gate effect) and Schottky barrier effect, depending on the place where biomolecules are adsorbed — will be covered.

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Biologically sensitive field-effect transistors: from ISFETs to NanoFETs

Essays in Biochemistry ◽

10.1042/ebc20150009 ◽

2016 ◽

Vol 60 (1) ◽

pp. 81-90 ◽

Cited By ~ 45

Author(s):

Vivek Pachauri ◽

Sven Ingebrandt

Keyword(s):

Field Effect ◽

Gate Dielectric ◽

Gate Dielectrics ◽

Field Effect Transistors ◽

Silicon Nanowire ◽

Label Free ◽

Biomolecular Detection ◽

New Device ◽

Label Free Detection ◽

History Of

Biologically sensitive field-effect transistors (BioFETs) are one of the most abundant classes of electronic sensors for biomolecular detection. Most of the time these sensors are realized as classical ion-sensitive field-effect transistors (ISFETs) having non-metallized gate dielectrics facing an electrolyte solution. In ISFETs, a semiconductor material is used as the active transducer element covered by a gate dielectric layer which is electronically sensitive to the (bio-)chemical changes that occur on its surface. This review will provide a brief overview of the history of ISFET biosensors with general operation concepts and sensing mechanisms. We also discuss silicon nanowire-based ISFETs (SiNW FETs) as the modern nanoscale version of classical ISFETs, as well as strategies to functionalize them with biologically sensitive layers. We include in our discussion other ISFET types based on nanomaterials such as carbon nanotubes, metal oxides and so on. The latest examples of highly sensitive label-free detection of deoxyribonucleic acid (DNA) molecules using SiNW FETs and single-cell recordings for drug screening and other applications of ISFETs will be highlighted. Finally, we suggest new device platforms and newly developed, miniaturized read-out tools with multichannel potentiometric and impedimetric measurement capabilities for future biomedical applications.

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Label-free detection of DNA hybridization using carbon nanotube network field-effect transistors

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.0504146103 ◽

2006 ◽

Vol 103 (4) ◽

pp. 921-926 ◽

Cited By ~ 521

Author(s):

A. Star ◽

E. Tu ◽

J. Niemann ◽

J.-C. P. Gabriel ◽

C. S. Joiner ◽

...

Keyword(s):

Carbon Nanotube ◽

Dna Hybridization ◽

Field Effect ◽

Field Effect Transistors ◽

Label Free ◽

Label Free Detection ◽

Carbon Nanotube Network

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Aptamer-Based Label-Free Immunosensors Using Carbon Nanotube Field-Effect Transistors

Electroanalysis ◽

10.1002/elan.200804552 ◽

2009 ◽

Vol 21 (11) ◽

pp. 1285-1290 ◽

Cited By ~ 92

Author(s):

Kenzo Maehashi ◽

Kazuhiko Matsumoto ◽

Yuzuru Takamura ◽

Eiichi Tamiya

Keyword(s):

Carbon Nanotube ◽

Field Effect ◽

Field Effect Transistors ◽

Label Free

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Detection of Tumor Markers Using Single-Walled Carbon Nanotube Field Effect Transistors

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2006.17969 ◽

2006 ◽

Vol 6 (11) ◽

pp. 3499-3502 ◽

Cited By ~ 2

Author(s):

Dong-Won Park ◽

Yo-Han Kim ◽

Beom Soo Kim ◽

Hye-Mi So ◽

Keehoon Won ◽

...

Keyword(s):

Carbon Nanotube ◽

Tumor Markers ◽

Field Effect ◽

Field Effect Transistors ◽

Sharp Decrease ◽

Tween 20 ◽

Label Free ◽

Single Walled Carbon Nanotube ◽

Single Walled Carbon ◽

Specific Tumor

We have developed a biosensor capable of detecting carcinoembryonic antigen (CEA) markers using single-walled carbon nanotube field effect transistors (SWNT-FETs). These SWNT-FETs were fabricated using nanotubes produced by a patterned catalyst growth technique, where the top contact electrodes were generated using conventional photolithography. For biosensor applications, SU-8 negative photoresist patterns were used as an insulation layer. CEA antibodies were employed as recognition elements to specific tumor markers, and were successfully immobilized on the sides of a single-walled carbon nanotube using CDI-Tween 20 linking molecules. The binding of tumor markers to these antibody-functionalized SWNT-FETs was then monitored continuously during exposure to dilute CEA solutions. The observed sharp decrease in conductance demonstrates the possibility of realizing highly sensitive, label-free SWNT-FET-based tumor sensors.

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Detection of C-Reactive Protein by Liquid-Gated Carbon Nanotube Field Effect Transistors (LG-CNTFET): A Promising Tool against Antibiotic Resistance

Engineering Proceedings ◽

10.3390/i3s2021dresden-10114 ◽

2021 ◽

Vol 6 (1) ◽

pp. 15

Author(s):

Luis Antonio Panes-Ruiz ◽

Tom Stückemann ◽

Leif Riemenschneider ◽

Markus Löffler ◽

Viktor Bezugly ◽

...

Keyword(s):

Carbon Nanotube ◽

Field Effect ◽

Bacterial Infections ◽

Field Effect Transistors ◽

High Sensitivity ◽

C Reactive Protein ◽

Reactive Protein ◽

Promising Tool ◽

Potential Biomarker ◽

Tract Infections

Respiratory tract infections have the highest rates of antibiotic prescriptions where symptoms like fever, cough, and rigors are regularly misinterpreted and where bacterial infections cannot be distinguished from viral ones. Nevertheless, it has been recently suggested that C-reactive protein (CRP), a protein produced by the liver in response to infection, could serve as a potential biomarker for the precise differentiation of these two types of infections. Thus, its quick and accurate detection would potentially reduce the unnecessary antibiotic use. To this end, we present an easy and sensitive approach for the selective detection of C-reactive protein (CRP) by liquid-gated carbon nanotube field effect transistors (LG-CNTFET). Herein, CNT-networks were deposited between electrodes via controlled dielectrophoretic deposition and then functionalized with a novel specific antibody and a polyethylene glycol (PEG) layer in order to overcome the Debye screening. The successful fabrication and functionalization were confirmed by scanning electron microscopy. The results showed a selective and reproducible detection down to picomolar concentrations in PBS buffer without complicated microfluidics. The simplicity and high sensitivity of this sensor platform make it a promising tool for the quick and precise differential diagnosis of viral and bacterial infections.

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Sensitivity Analysis of Biosensors Based on a Dielectric-Modulated L-Shaped Gate Field-Effect Transistor

Micromachines ◽

10.3390/mi12010019 ◽

2020 ◽

Vol 12 (1) ◽

pp. 19

Author(s):

Chen Chong ◽

Hongxia Liu ◽

Shulong Wang ◽

Shupeng Chen ◽

Haiwu Xie

Keyword(s):

Power Consumption ◽

Field Effect ◽

Field Effect Transistors ◽

Vertical Direction ◽

High Sensitivity ◽

Subthreshold Swing ◽

Voltage Sensitivity ◽

Label Free ◽

Current Sensitivity ◽

Sensor Field

Label-free biomolecular sensors have been widely studied due to their simple operation. L-shaped tunneling field-effect transistors (LTFETs) are used in biosensors due to their low subthreshold swing, off-state current, and power consumption. In a dielectric-modulated LTFET (DM-LTFET), a cavity is trenched under the gate electrode in the vertical direction and filled with biomolecules to realize the function of the sensor. A 2D simulator was utilized to study the sensitivity of a DM-LTFET sensor. The simulation results show that the current sensitivity of the proposed structure could be as high as 2321, the threshold voltage sensitivity could reach 0.4, and the subthreshold swing sensitivity could reach 0.7. This shows that the DM-LTFET sensor is suitable for a high-sensitivity, low-power-consumption sensor field.

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Label-Free DNA Biosensors Based on Functionalized Carbon Nanotube Field Effect Transistors

Nano Letters ◽

10.1021/nl8025604 ◽

2009 ◽

Vol 9 (2) ◽

pp. 530-536 ◽

Cited By ~ 130

Author(s):

Maria Teresa Martínez ◽

Yu-Chih Tseng ◽

Nerea Ormategui ◽

Iraida Loinaz ◽

Ramon Eritja ◽

...

Keyword(s):

Carbon Nanotube ◽

Field Effect ◽

Field Effect Transistors ◽

Label Free ◽

Dna Biosensors ◽

Free Dna ◽

Functionalized Carbon Nanotube

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Effect of channel length on the electrical response of carbon nanotube field-effect transistors to deoxyribonucleic acid hybridization

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.5.217 ◽

2014 ◽

Vol 5 ◽

pp. 2081-2091 ◽

Cited By ~ 7

Author(s):

Hari Krishna Salila Vijayalal Mohan ◽

Jianing An ◽

Yani Zhang ◽

Chee How Wong ◽

Lianxi Zheng

Keyword(s):

Carbon Nanotube ◽

Field Effect ◽

Field Effect Transistors ◽

Electrical Response ◽

Channel Length ◽

Nucleic Acid Hybridization ◽

Label Free ◽

Single Walled Carbon Nanotube ◽

Label Free Detection ◽

Simultaneous Influence

A single-walled carbon nanotube (SWCNT) in a field-effect transistor (FET) configuration provides an ideal electronic path for label-free detection of nucleic acid hybridization. The simultaneous influence of more than one response mechanism in hybridization detection causes a variation in electrical parameters such as conductance, transconductance, threshold voltage and hysteresis gap. The channel length (L) dependence of each of these parameters necessitates the need to include them when interpreting the effect of L on the response to hybridization. Using the definitions of intrinsic effective mobility (µe) and device field-effect mobility (µf), two new parameters were defined to interpret the effect of L on the FET response to hybridization. Our results indicate that FETs with ≈300 µm long SWCNT exhibited the most appreciable response to hybridization, which complied with the variation trend in response to the newly defined parameters.

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