Integrated peptide receptor / carbon nanotube-based TNT sensor
We have developed a highly selective and ultra sensitive TNT sensor. The high selectivity arises from the tripeptide TNT receptors developed within COINS. The single-wall carbon nanotube field effect transistor (SWNT-FET) provides the ultra sensitivity. The tripeptide TNT receptor was discovered through phage display. The newly developed PDA-TNT receptor coating materials exhibit very efficient transduction of selective binding events between the WHW receptors and target TNT, enabling the development of sensitive SWNT-FET sensors. The resulting sensors reproducibly exhibited excellent selectivity with 1 fM sensitivity in real time. The devices also showed good selectivity for other explosives molecules having chemical structures similar to TNT [e.g., DNT (dinitrotoluene), 2NT (2-nitrotoluene) and 4NT (4-nitrotoluene)]. This integrated device fulfills the sensing needs of selectivity and sensitivity, while providing a low power measurement scheme.