Ionic liquid carbon nanotube composites for wireless chemical sensing

Abstract

A wireless sensor platform design and a single walled carbon nanotube/ionic liquid-based chemidosimeter system can incorporated into a highly sensitive and selective chemical hazard badge that can dosimetrically detect an analyte down to a sub parts-per-million concentration.

What is claimed is: 
     
         1 . A device for detecting a stimulus comprising:
 a radio frequency identification tag including a sensor portion including:
 an integrated circuit; and 
 a chemiresistor, 
 wherein the integrated circuit and the chemiresistor are connected in parallel, 
   wherein the sensor portion is configured to change resistivity when the radio frequency identification tag contacts or interacts with the stimulus, whereby the resistivity change alters an output of the radio frequency identification tag, and wherein the sensor portion is configured to activate the circuit or deactivate the circuit when contacted or having interacted with the stimulus.   
     
     
         2 . The device of  claim 1 , wherein the chemiresistor includes a plurality of nanotubes. 
     
     
         3 . The device of  claim 2 , wherein the chemiresistor further includes an ionic liquid. 
     
     
         4 . The device of  claim 1 , wherein the device is a badge wearable by a person. 
     
     
         5 . The device of  claim 4 , wherein the badge is for a single-use. 
     
     
         6 . The device of  claim 2 , wherein the nanotubes are single walled carbon nanotubes. 
     
     
         7 . The device of  claim 3 , wherein the ionic liquid is 1-butyl-3-methylimidazolium chloride. 
     
     
         8 . The device of  claim 1 , wherein the stimulus includes an analyte. 
     
     
         9 . The device of  claim 1 , wherein the analyte is diethyl chlorophosphate. 
     
     
         10 . A system for detecting a stimulus comprising the device of  claim 1  and a reader detecting the output from the radio frequency identification tag. 
     
     
         11 . The system of  claim 10 , wherein the reader is a handheld reader. 
     
     
         12 . The system of  claim 11 , wherein the handheld reader is a smartphone. 
     
     
         13 . The system of  claim 9 , wherein the system includes a dosimeter. 
     
     
         14 . The system of  claim 13 , wherein the system includes a plurality of tags. 
     
     
         15 . The system of  claim 14 , wherein each of the plurality of tags is capable of detecting at least one stimulus. 
     
     
         16 . A food packaging including the device of  claim 1 . 
     
     
         17 . A breath analysis detector including the device of  claim 1 . 
     
     
         18 . A humidity sensor including the device of  claim 1 , 
     
     
         19 . A method of detecting a stimulus comprising:
 detecting an output from a radio frequency identification tag including a sensor portion including:
 an integrated circuit; and 
 a chemiresistor, 
 wherein the integrated circuit and the chemiresistor are connected in parallel, 
   wherein the sensor portion is configured to change resistivity when the radio frequency identification tag contacts or interacts with the stimulus, whereby the resistivity change alters an output of the radio frequency identification tag, and wherein the sensor portion is configured to activate the circuit or deactivate the circuit when contacted or having interacted with the stimulus.   
     
     
         20 . The method of  claim 19 , further comprising detecting the output of the radio frequency identification by a reader. 
     
     
         21 . The method of  claim 20 , wherein the reader is a hand-held reader. 
     
     
         22 . The method of  claim 21 , wherein the reader includes a smartphone. 
     
     
         23 . The method of  claim 19 , wherein the chemiresistor includes a plurality of nanotubes. 
     
     
         24 . The method of  claim 23 , wherein the chemiresistor further includes an ionic liquid. 
     
     
         25 . The method of  claim 23 , wherein the nanotubes are single walled carbon nanotubes. 
     
     
         26 . The method of  claim 24 , wherein the ionic liquid is 1-butyl-3-methylimidazolium chloride. 
     
     
         27 . The method of  claim 19 , wherein the stimulus includes an analyte. 
     
     
         28 . The method of  claim 27 , wherein the analyte is diethyl chlorophosphate. 
     
     
         29 . The method of  claim 19 , further comprising producing a readable signal in a reader as a result of the resistivity change. 
     
     
         30 . The method of  claim 19 , further comprising turning off a readable signal in a reader as a result of the resistivity change 
     
     
         31 . The method of  claim 19 , wherein the output is detectable by a reader after the output is shifted by detection of the stimulus. 
     
     
         32 . The method of  claim 19 , wherein the output is detectable by a reader after the output going through a physical object. 
     
     
         33 . The method of  claim 19 , wherein the stimulus contacts or interacts with a portion of the surface of the radio frequency identification tag. 
     
     
         34 . The method of  claim 19 , wherein the radio frequency identification tag does not require a power source. 
     
     
         35 . The method of  claim 19 , further comprising altering an electrical connection within the radio frequency identification tag. 
     
     
         36 . The device of  claim 1 , wherein the sensor portion further comprises a resistor in series with the integrated circuit. 
     
     
         37 . The device of  claim 36 , wherein the resistor sets a threshold at which the integrated circuit is activated. 
     
     
         37 . The device of  claim 1 , wherein the chemiresistor includes a plurality of conducting polymers