title: Ultratrace Detection of Toxic Chemicals: Triggered Disassembly of Supramolecular Nanotube Wrappers.
abstract: Chemical sensors offer opportunities for improving personal security, safety, and health. To enable broad adoption of chemical sensors requires performance and cost advantages that are best realized from innovations in the design of the sensing (transduction) materials. Ideal materials are sensitive and selective to specific chemicals or chemical classes and provide a signal that is readily interfaced with portable electronic devices. Herein we report that wrapping single walled carbon nanotubes with metallo-supramolecular polymers creates sensory devices with a dosimetric (time- and concentration-integrated) increase in electrical conductivity that is triggered by electrophilic chemical substances such as diethylchlorophosphate, a nerve agent simulant. The mechanism of this process involves the disassembly of the supramolecular polymer, and we demonstrate its utility in a wireless inductively powered sensing system based on near-field communication technology. Specifically, the dosimeters can be powered and read wirelessly with conventional smartphones to create sensors with ultratrace detection limits.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology (MIT) , Cambridge, Massachusetts 02139, United States.|International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS) , Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Ishihara
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology (MIT) , Cambridge, Massachusetts 02139, United States.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Azzarelli
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology (MIT) , Cambridge, Massachusetts 02139, United States.
authors.forename: Markrete
authors.initials: M
authors.lastname: Krikorian
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology (MIT) , Cambridge, Massachusetts 02139, United States.
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Swager
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004553:Electric Conductivity; D057230:Limit of Detection; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009943:Organophosphorus Compounds / Q000032:analysis* / Q000737:chemistry; D010091:Oximes / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D013461:Sulfur Oxides / Q000737:chemistry; D059015:Wireless Technology
chemical_list: D037742:Nanotubes, Carbon; D009943:Organophosphorus Compounds; D010091:Oximes; D011108:Polymers; D013461:Sulfur Oxides; C548970:diethylchlorophosphate; C023589:thionyl chloride