An inkjet-printed field-effect transistor for label-free biosensing

August 11, 2014
A flexible Bio-Field Effect Transistor (BioFET), fabricated mostly by using inkjet printing technology is reported as an alternative transducer for protein detection. The device is characterized in diverse ways and it was applied as a protein label-free sensor as a proof of concept. Credit: Catalan Institute of Nanoscience and Nanotechnology

Thin-film transistors (TFTs) are powerful devices in semiconductor manufacturing and form the basis of countless electronic devices, such as memory chips, photovoltaic cells, logic gates, and sensors. An interesting alternative to inorganic TFTs (silicon) is organic TFTs (OTFTs), which offer the possibility of mass production by using the conventional printing technology and working with low-cost materials. However, numerous inherent problems still remain, especially concerning the long-term stability and lack of reliability.

Researchers from the Institut Català de Nanociència i Nanotecnologia's (ICN2 – Catalan Institute of Nanoscience and Nanotechnology) Nanobioelectronics and Biosensors Group, led by the ICREA Research Prof Arben Merkoçi, work to get OTFTs closer to devices which can be fully applied in field applications. The Group published in the last issue of Advanced Functional Materials an article describing a flexible, biological field-effect transistor (BioFET) for use in biosensing. The fabrication, structure, materials optimization, electrical characteristics, and functionality of the starting OTFT and final BioFET are also discussed. The authors of the article are Dr Mariana Medina-Sánchez, Dr Carme Martínez-Domingo, Dr Eloi Ramon[, and ICREA Research Prof Arben Merkoçi.

A fully integrated organic BioFET was designed, fabricated and tested for label-free protein detection. It was made by inkjet printing of an organic field-effect transistor (OFET) and subsequent functionalization of the insulator with specific antibodies. ICN2 researchers analysed different insulators, the biofunctionalization of the surface, the selective adhesion of target proteins to the BioFET, the repeatability with different devices and the roughness of functionalized and immobilized protein structures. Finally, as proof of concept, the BioFET platform was successfully tested for detection of the model protein, human immunoglobulin G (HIgG).

The BioFET designed at ICN2 represents an important starting point for the design and fabrication of flexible, organic biosensing devices by inkjet printing. The reproducibility in the fabrication process, the development of functional inks and extension of this technology to a wider array of substrates are still unsolved issues. The authors are confident that once this technology has matured, it will be amenable to miniaturization for integration into a fully functional for point-of-care diagnosis.

Explore further: Breakthrough reported in transconductance in ink-jet printing

More information: Mariana Medina-Sánchez, Carme Martínez-Domingo, Eloi Ramon, Arben Merkoçi. An Inkjet-Printed Field-Effect Transistor for Label-Free Biosensing. Advanced Functional Materials. Article first published online: 31 JUL 2014. DOI: 10.1002/adfm.201401180

Related Stories

Move over, silicon, there's a new circuit in town

June 17, 2014

( —When it comes to electronics, silicon will now have to share the spotlight. In a paper recently published in Nature Communications, researchers from the USC Viterbi School of Engineering describe how they have ...

A cool approach to flexible electronics

July 10, 2014

A nanoparticle ink that can be used for printing electronics without high-temperature annealing presents a possible profitable approach for manufacturing flexible electronics.

Recommended for you

Nanoparticle ink could combat counterfeiting

February 5, 2016

(—Researchers have demonstrated that transparent ink containing gold, silver, and magnetic nanoparticles can be easily screen-printed onto various types of paper, with the nanoparticles being so small that they ...

Graphene is strong, but is it tough?

February 4, 2016

Graphene, a material consisting of a single layer of carbon atoms, has been touted as the strongest material known to exist, 200 times stronger than steel, lighter than paper, and with extraordinary mechanical and electrical ...

Tiniest spin devices becoming more stable

February 3, 2016

(—In 2011, the research group of Roland Wiesendanger, Physics Professor at the University of Hamburg in Germany, fabricated a spin-based logic device using the spins of single atoms, a feat that represents the ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.