Set 092015
 

The role of polarization-induced reorientation of DNA strands on organic field-effect transistor-based biosensors sensitivity at high ionic strength

Stefano Lai, Massimo Barbaro, Annalisa Bonfiglio

Appl. Phys. Lett. 107, 103301 (2015)

The detection of the intrinsic charge of biochemical molecules is a promising strategy for the fabrication of field-effect transistor (FET)-based sensors for direct, non-destructive detection of several biochemical reactions. Nevertheless, the high ionic concentration of standard environments for biochemical species represents a significant limitation to this sensing strategy. Here, an investigation on the physical mechanisms behind the ability of an organic FET-based sensor to detect DNA hybridization at high ionic strengths is proposed. The capability of the device to correctly detect single-stranded DNA oligonucleotides and their hybridization with a complementary target sequence has been analyzed in detail. In particular, the electrical response in solutions with different ionic strengths was investigated and put in relation with the nano-scale properties of DNA strands employed as receptors. Fluorescence analysis shows that it is possible to electrically modify their orientation and consequently improve the device sensitivity in conditions close to those occurring during hybridization.

 Scritto da in 9 settembre 2015  Avvisi  Commenti disabilitati su NEW PUBLICATION:”The role of polarization-induced reorientation of DNA strands on organic field-effect transistor-based biosensors sensitivity at high ionic strength”
Set 022015
 

Self-encapsulation of organic thin film transistors by means of ion implantation

P. Cosseddu, B. Fraboni, A. Scidà, Y.Q. Wang, M. Nastasi, A. Bonfiglio

Synthetic Metals, Volume 209, November 2015, Pages 178-182

doi:10.1016/j.synthmet.2015.07.018

Long-term stability of devices based on organic materials is still impeding the diffusion of these structures in real applications. In this paper we have investigated the effects of low energy, combined, ion implantation (N and Ne) in the evolution of the electrical performances of pentacene-based Organic Thin Film Transistors (OTFTs) over time by means of current–voltage and photocurrent spectroscopy analyses. We have demonstrated that the selected combination of ions allows reducing the degradation of charge carriers mobility, and also stabilization of the devices threshold voltage over a long time (over 2000 h).

 Scritto da in 2 settembre 2015  Avvisi  Commenti disabilitati su NEW PUBLICATION: “Self-encapsulation of organic thin film transistors by means of ion implantation”
credits unica.it | accessibilità Università degli Studi di Cagliari
C.F.: 80019600925 - P.I.: 00443370929
note legali | privacy

Nascondi la toolbar