Detection of biomolecules by using liquid-gate carbon nanotubes based field effect transistors

Abstract

Single walled carbon nanotubes (SWCNTs) have sparked considerable interest in biosensing applications due to their exceptional charge transport properties and size compatibility (diameter of ~1 nm) with biomolecules. Charges being confined to the nanotube surface are able to detect molecular level changes in their immediate environment and have been exploited in label-free field effect transistor (FET) based biosensors for detection of proteins, peptides, and DNA amongst others. Whereas most significant studies thus far have focused on silicon substrate supported CNTs, often in the dry-state, this thesis introduces a PDMS supported liquid-gated CNT based FET (PDMS based LG-CNTFET) platform. This new device concept based on an all-plastic construction, integrates a microfluidic platform into the CNT FET based immunosensor, and demonstrates great potential towards the realization of point-of-care diagnostic and on-site sample analysis systems well-suited as disposable sensor kits required in environmental sensing as well as medical diagnostics.