Sensors and sensor arrays of conducting and insulating composites and methods of use thereof

Abstract

The present invention provides a class of sensors prepared from at least a first material having a positive temperature coefficient of resistance and a second non-conductive or insulating material compositionally different than the first material that show an increase sensitivity detection limit for polar and non-polar analytes. The sensors have applications in the detection of analytes in the environment, associated with diseases and microorganisms.

1 - 3 . (canceled)  
   
   
       4 . A sensor array comprising: 
 a plurality of sensors; and    a measuring apparatus, wherein the sensors are in communication with the measuring apparatus,    at least one sensor comprising:    regions of at least a first material having a positive temperature coefficient of resistance and a second non-conductive or insulating material compositionally different than the first material, wherein the sensor provides an electrical path through the regions of the first material and the regions of the second material, the first material being selected from the group consisting of a polyaniline, an emeraldine salt of polyaniline, a polythiophene, a poly(3,4-ethylenedioxy)thiophene (polyEDOT), a poly(3,4-ethylenedithiathiophene), and a poly(3,4-ethylenedioxy)thiophene-poly(styrene sulfonate) (PEDOT-PSS), the sensors constructed to provide a first response when contacted with a first analyte, and a second different response when contacted with a second different analyte.    
   
   
       5 . The sensor array of  claim 4 , wherein the measuring apparatus is an electrical measuring device in electrical communication with at least one sensor.  
   
   
       6 . The sensor array according to  claim 4 , wherein the array comprises a plurality of sensors, at least one sensor having regions of a non-conductive material that is compositionally different than the non-conductive material of at least one other sensor.  
   
   
       7 . The sensor array according to  claim 4 , wherein the array comprise a plurality of sensors, at least one sensor having regions of a first material that is compositionally different than the first material of at least one other sensor.  
   
   
       8 . The sensor array according to  claim 4 , wherein the response is a change in resistance in the sensors.  
   
   
       9 . The sensor array according to  claim 4 , wherein the first material of the plurality of sensors are compositionally the same or compositionally different.  
   
   
       10 . The sensor array according to  claim 4 , further comprising a temperature control apparatus, the temperature control apparatus in thermal communication with at least one sensor.  
   
   
       11 . The sensor array according to  claim 10 , wherein the resistance of the sensor is R m  at temperature T m  when contacted with a chemical analyte, where m is an integer greater than 1.  
   
   
       12 . The sensor array according to  claim 4 , wherein the response is a change in impedance.  
   
   
       13 . The sensor array according to  claim 4 , wherein a sensor in the array contains an inorganic conductor selected form the group consisting of Ag, Au, Cu, Pt, carbon black, and AuCu.  
   
   
       14 . A sensor array system comprising: 
 a plurality of sensors, comprising regions of at least a first material having a positive temperature coefficient of resistance and a second non-conductive or insulating material compositionally different than the first material, wherein the sensor provides an electrical path through the regions of the first material and the regions of the second material, the first material being selected from the group consisting of a polyaniline, an emeraldine salt of polyaniline, a polythiophene, a poly (3,4-ethylenedioxy)thiophene (polyEDOT), a poly(3,4-ethylenedithiathiophene), and a poly(3,4-ethylenedioxy)thiophene-poly(styrene sulfonate) (PEDOT-PSS);    a measuring apparatus, wherein the plurality of sensor s are in communication with the measuring apparatus; and    a computer comprising a resident algorithm,    the sensors constructed to provide a first response when contacted with a first analyte, and a second different response when contacted with a second different analyte, wherein the computer processes the difference between the first response and the second response.    
   
   
       15 . The system of  claim 14 , wherein the analyte is detected in an application which is selected from the group consisting of environmental toxicology, remediation, biomedicine, material quality control, food monitoring, agricultural monitoring, heavy industrial manufacturing, ambient air monitoring, worker protection, emissions control, product quality testing, oil/gas petrochemical applications, combustible gas detection, H 2 S monitoring, hazardous leak detection, emergency response and law enforcement applications, explosives detection, utility and power applications, food/beverage/agriculture applications, freshness detection, fruit ripening control, fermentation process monitoring and control, flavor composition and identification, product quality and identification, refrigerant and fumigant detection, cosmetic/perfume applications, fragrance formulation, chemical/plastics/pharmaceuticals applications, fugitive emission identification, solvent recovery effectiveness, hospital/medical applications, anesthesia and sterilization gas detection, infectious disease detection, breath analysis and body fluids analysis.  
   
   
       16 . The system in accordance with  claim 14 , wherein the array of sensors further comprises a member selected from the group consisting of a surface acoustic wave sensor, a quartz microbalance sensor; a conductive composite; a chemiresistor; a metal oxide gas sensor and a conducting polymer sensor, a dye-impregnated polymer film on fiber optic detector, a polymer-coated micromirror, an electrochemical gas detector, a chemically sensitive field-effect transistor, a carbon black-polymer composite, a micro-electro-mechanical system device and a micro-optoelectro-mechanical system device.  
   
   
       17 - 30 . (canceled)