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

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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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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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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Sequence-dependent electrical response of ssDNA-decorated carbon nanotube, field-effect transistors to dopamine

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.5.220 ◽

2014 ◽

Vol 5 ◽

pp. 2113-2121 ◽

Cited By ~ 3

Author(s):

Hari Krishna Salila Vijayalal Mohan ◽

Jianing An ◽

Lianxi Zheng

Keyword(s):

Carbon Nanotube ◽

Field Effect ◽

Field Effect Transistors ◽

Electrical Response ◽

Disease Diagnosis ◽

Electrical Parameters ◽

Single Walled Carbon Nanotube ◽

Sequence Dependent ◽

Base Sequences ◽

Different Response

Single-walled carbon nanotube (SWCNT)-based field-effect transistors (FETs) have been explored for use as biological/chemical sensors. Dopamine (DA) is a biomolecule with great clinical significance for disease diagnosis, however, SWCNT FETs lack responsivity and selectivity for its detection due to the presence of interfering compounds such as uric acid (UA). Surface modification of CNTs using single-stranded deoxyribonucleic acid (ssDNA) renders the surface responsive to DA and screens the interferent. Due to the presence of different bases in ssDNA, it is necessary to investigate the effect of sequence on the FET-based molecular recognition of DA. SWCNT FETs were decorated with homo- and repeated-base ssDNA sequences, and the electrical response induced by DA in the presence and absence of UA was gauged in terms of the variation in transistor electrical parameters including conductance, transconductance, threshold voltage and hysteresis gap. Our results showed that the response of ssDNA-decorated devices to DA, irrespective of the presence or absence of UA, was DNA sequence dependent and exhibited the trend: G > A > C and GA > GT > AC > CT, for homo- and repeated-base sequences, respectively. The different response of various SWCNT–ssDNA systems to DA underlines the sequence selectivity, whereas the detection of DA in the presence of UA highlights the molecular selectivity of the ssDNA-decorated devices.

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Affinity Sensors for the Diagnosis of COVID-19

Micromachines ◽

10.3390/mi12040390 ◽

2021 ◽

Vol 12 (4) ◽

pp. 390

Author(s):

Maryia Drobysh ◽

Almira Ramanaviciene ◽

Roman Viter ◽

Arunas Ramanavicius

Keyword(s):

Field Effect Transistors ◽

Resonance Field ◽

Analytical Signal ◽

Nucleic Acid Hybridization ◽

Detection Methods ◽

Label Free ◽

Infected People ◽

Label Free Detection ◽

Main Instrument ◽

Antigen Antibody

The coronavirus disease 2019 (COVID-19) outbreak caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was proclaimed a global pandemic in March 2020. Reducing the dissemination rate, in particular by tracking the infected people and their contacts, is the main instrument against infection spreading. Therefore, the creation and implementation of fast, reliable and responsive methods suitable for the diagnosis of COVID-19 are required. These needs can be fulfilled using affinity sensors, which differ in applied detection methods and markers that are generating analytical signals. Recently, nucleic acid hybridization, antigen-antibody interaction, and change of reactive oxygen species (ROS) level are mostly used for the generation of analytical signals, which can be accurately measured by electrochemical, optical, surface plasmon resonance, field-effect transistors, and some other methods and transducers. Electrochemical biosensors are the most consistent with the general trend towards, acceleration, and simplification of the bioanalytical process. These biosensors mostly are based on the determination of antigen-antibody interaction and are robust, sensitive, accurate, and sometimes enable label-free detection of an analyte. Along with the specification of biosensors, we also provide a brief overview of generally used testing techniques, and the description of the structure, life cycle and immune host response to SARS-CoV-2, and some deeper details of analytical signal detection principles.

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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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