Flexible pentacene thin film transistors as DNA hybridization sensor

A DNA hybridization sensor using pentacene thin film transistors (TFTs) is an excellent candidate for disposable sensor applications due to their low-cost fabrication process and fast detection. We fabricated pentacene TFTs on flexible substrate for the sensing of DNA hybridization. The 100 mer ss-DNA (poly A/poly T) or 100 bp ds-DNA (poly A/poly T hybrid) are deposited from a solution on pentacene layer. The electrical characteristics of devices were studied as a function of DNA immobilization, single- and double-strand DNA and DNA concentrations. The DNA molecules were immobilized directly on the surface of the pentacene, thereby producing a dramatic change in the electrical properties of the devices. Based on these results, we propose that a “label-free” detection technique for DNA hybridization is possible through direct measurement of electrical properties by the immobilization of DNA on pentacene TFTs.