Ultrasensitive, label-free, and real-time immunodetection using silicon field-effect transistors

Label-free and real-time detection technologies can dramatically reduce the time and cost of pharmaceutical testing and development. However, to reach their full promise, these technologies need to be adaptable to high-throughput automation. To demonstrate the potential of single-walled carbon nanotube field-effect transistors (SWCNT-FETs) for high-throughput peptide-based assays, we have designed circuits arranged in an 8 × 12 (96-well) format that are accessible to standard multichannel pipettors. We performed epitope mapping of two HIV-1 gp160 antibodies using an overlapping gp160 15-mer peptide library coated onto nonfunctionalized SWCNTs. The 15-mer peptides did not require a linker to adhere to the non-functionalized SWCNTs, and binding data was obtained in real time for all 96 circuits. Despite some sequence differences in the HIV strains used to generate these antibodies and the overlapping peptide library, respectively, our results using these antibodies are in good agreement with known data, indicating that peptides immobilized onto SWCNT are accessible and that linear epitope mapping can be performed in minutes using SWCNT-FET.

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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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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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