Label-free biosensor for detection of specific protein based on carbon nanotubes network thin film transistor

A proof of concept of a thin film transistor (TFT) based on network of 99% semiconducting single walled carbon nanotubes (SWCNTs) is fabricated to show its applicability as a low cost biosensor for detecting specific molecules. The binding of biotin and streptavidin is used as a research model for evaluating sensor effectiveness. The biosensor response is based on the current modulation through interaction of biotinylated-SWCNTs in the channel of TFT structure with streptavidin. The proposed biosensor, whose fabrication process is carried out at room temperature, shows a successful immobilization of streptavidin with sensitivity detection as low as 100 pM. This new biosensor provides great potential for label-free detection of a wide range of biomolecules in applications such as array based screening.