Transcript **** 1 - unist

Selective and Sensitive Trinitrotoluene Detection using Phage
Display Derived Coatings on CNT-FET Based Sensors
Speaker : Justyn Jaworski, Ph.D
Gyeongsang National University
Susceptibility of chemical sensors to false positive signals remains a common
drawback due to insufficient sensor coating selectivity. Using phage display, we
have mimicked biology to create a sequence-specific peptide based receptor
capable of highly selective recognition of trinitrotoluene (TNT). Using mutational
analysis, we show that the identified binding peptides recognize the target substrate
through multivalent binding with key amino acid residues. By covalently linking
conjugated polydiacetylene (PDA) with our peptide-based receptor for TNT, we
created a polymeric coating capable of selectively responding to the presence of a
TNT target. The response created by the coating is a change in conformation of the
conjugated polymer backbone due to TNT binding. When implementing this
coating onto single-walled carbon nanotube-field effect transistors (SWNT-FET),
we were able to identify the conformational change of the polymer as a change in
conductance. Therefore, selective binding events between the TNT molecules and
phage display derived TNT receptors were effectively transduced to the sensitive
SWNT-FET conductance sensors through a PDA coating. The resulting sensors
exhibited an unprecedented 1 fM sensitivity toward TNT in real time, with
excellent selectivity over various similar aromatic compounds. This modular
biomimetic receptor coating approach may be useful for the development of other
sensitive and selective micro and nanoelectronic sensor devices for various target
chemicals of interest.
When: 4:00 PM on May 30 (MON)
Where: Engineering Building 1, E104
Contact: Prof . Sung Kuk Lee (2516) / [email protected]
School of Nano-Bioscience & Chemical Engineering
UNIST