Chemical sensors provides improvement of home land security and public safety. One of technological challenges is design of innovative sensing materials, whose selective chemical interaction with a molecular analyte can be sensitively readout by a low cost and portable electronic device. Herein, we present that carbon nanotube (CNT) functionalized with supramolecular polymer (SP) demonstrates amplified and time-integrated increase in electrical conductivity when exposed to electrophilic chemical substances including diethyl chlorophosphate (DECP), a nerve agent simulant. Our SWCNT-SP composite material demonstrate over 1000% increase of electronic conductivity upon exposure to sub-ppm order of DECP, while pristine SWCNT demonstrate negligible response. Owing to an enormous and irreversible sensing response, our material is compatible with a wireless sensing system based on near field communication technology. Thus, commercial smartphone can be employed for facile detection of harmful vapors in air.