Highly selective chemical and biological sensors

Abstract

Methods and sensors for selective fluid sensing are provided. A sensor includes a resonant inductor-capacitor-resistor (LCR) circuit and a sensing material disposed over the LCR circuit. The sensing material includes a coordination compound of a ligand and a metal nanoparticle. The coordination compound has the formula: (X) n -M, where X includes an alkylamine group having the formula (R—NH 2 ), an alkylphosphine having the formula (R 3 —P), an alkylphosphine oxide having the formula (R 3 P═O), an alkyldithiocarbamate having the formula (R 2 NCS 2 ), an alkylxanthate having the formula (ROCS 2 ), or any combination thereof, R includes an alkyl group, n is 1, 2, or 3, and M includes the metal nanoparticle of gold, silver, platinum, palladium, alloys thereof, highly conductive metal nanoparticles, or any combination thereof. The sensing material is configured to allow selective detection of at least six different analyte fluids from an analyzed fluid mixture.

1 . A sensor, comprising:
 a resonant inductor-capacitor-resistor (LCR) circuit; and   a sensing material disposed over the LCR circuit, wherein the sensing material comprises a coordination compound of a ligand and a metal nanoparticle, wherein:
 the coordination compound has the formula:
   ( X ) n - M , wherein: 
 X comprises an alkylamine group having the formula (R—NH 2 ), an alkylphosphine having the formula (R 3 —P), an alkylphosphine oxide having the formula (R 3 P═O), an alkyldithiocarbamate having the formula (R 2 NCS 2 ), an alkylxanthate having the formula (ROCS 2 ), or any combination thereof; 
 R comprises an alkyl group; 
 n is 1, 2, or 3; and 
 M comprises the metal nanoparticle, 
 
 wherein the sensing material is configured to allow selective detection of at least six different analyte fluids from an analyzed fluid mixture. 
   
     
     
         2 . The sensor, as set forth in  claim 1 , wherein the alkyl group has the formula:
     C   y   H   2y+1 , wherein  y= 1 to 18.   
     
     
         3 . The sensor, as set forth in  claim 1 , wherein the metal nanoparticle comprises gold, silver, platinum, palladium, alloys thereof, highly conductive metal nanoparticles, or any combination thereof. 
     
     
         4 . The sensor, as set forth in  claim 1 , comprising a memory chip. 
     
     
         5 . The sensor, as set forth in  claim 1 , wherein the sensor comprises an RFID sensor. 
     
     
         6 . The sensor, as set forth in  claim 1 , comprising a coil. 
     
     
         7 . The sensor, as set forth in  claim 1 , wherein the sensing material is disposed between electrodes of the LCR circuit. 
     
     
         8 . The sensor, as set forth in  claim 1 , wherein the sensor is configured to sense a first fluid in the analyzed fluid in the presence of a second fluid in the analyzed fluid, wherein a concentration of the second fluid is at least ten times greater than a concentration of the first fluid. 
     
     
         9 . A method of detecting chemical or biological species in a fluid, comprising:
 measuring a real part and an imaginary part of an impedance spectrum of a resonant sensor antenna coated with a coordination compound of a ligand and a metal nanoparticle, wherein the ligand comprises a primary alkyl amine, trialkylphosphine, trialkylphosphine oxide, alkyldithiocarbamate, alkylxanthate or any combination thereof;   calculating at least six spectral parameters of the resonant sensor antenna coated with the coordination compound;   reducing the impedance spectrum to a single data point using multivariate analysis to selectively identify an analyte; and   determining one or more environmental parameters from the impedance spectrum.   
     
     
         10 . The method, as set forth in  claim 9 , wherein the coordination compound has the formula:
   ( X ) n - M , wherein:   X comprises an alkylamine group having the formula (R—NH 2 ), an alkylphosphine having the formula (R 3 —P), an alkylphosphine oxide having the formula (R 3 P═O), an alkyldithiocarbamate having the formula (R 2 NCS 2 ), an alkylxanthate having the formula (ROCS 2 ), or any combination thereof;   R comprises an alkyl group, wherein the alkyl group has the formula C y H 2y+1 , wherein y=1 to 18;   n is 1, 2, or 3; and   M comprises the metal nanoparticle of gold, silver, platinum, palladium, alloys thereof, highly conductive metal nanoparticles, or any combination thereof.   
     
     
         11 . The method, as set forth in  claim 9 , wherein measuring the impedance spectrum and calculating at least six spectral parameters comprises measuring over a resonant frequency range of the resonant sensor. 
     
     
         12 . The method, as set forth in  claim 9 , wherein calculating at least six spectral parameters comprises calculating a frequency position of the real part of the impedance spectrum, and a magnitude of the real part of the impedance spectrum. 
     
     
         13 . The method, as set forth in  claim 9 , wherein calculating at least six spectral parameters comprises calculating a resonant frequency of the imaginary part of the impedance spectrum, and an anti-resonant frequency of the imaginary part of the impedance spectrum. 
     
     
         14 . The method, as set forth in  claim 9 , wherein determining comprises determining a resistance and a capacitance of the resonant sensor coated with the coordination compound. 
     
     
         15 . The method, as set forth in  claim 9 , wherein reducing the impedance spectrum to a single data point comprises calculating a multivariate signature. 
     
     
         16 . A sensor, comprising:
 a transducer having a multivariate output to independently detect effects of different environmental parameters on the sensor; and   a coordination compound of a ligand and a metal nanoparticle disposed on the transducer and having a preserved magnitude of response to an analyte over a broad concentration range of an interferent, wherein:
 the coordination compound has the formula:
   ( X ) n - M , wherein: 
 X comprises an alkylamine group having the formula (R—NH 2 ), an alkylphosphine having the formula (R 3 —P), an alkylphosphine oxide having the formula (R 3 P═O), an alkyldithiocarbamate having the formula (R 2 NCS 2 ), an alkylxanthate having the formula (ROCS 2 ), or any combination thereof; 
 R comprises an alkyl group; 
 n is 1, 2, or 3; and 
 M comprises the metal nanoparticle of gold, silver, platinum, palladium, alloys thereof, highly conductive metal nanoparticles, or any combination thereof. 
 
   
     
     
         17 . The sensor, as set forth in  claim 16 , wherein the coordination compound has multiple response mechanisms to analytes and interferents. 
     
     
         18 . The sensor, as set forth in  claim 17 , wherein the response mechanisms of the sensing material are related to the changes of dielectric constant, resistance, and swelling of the coordination compound where these changes are not fully correlated with each other and produce different patterns upon exposure to individual fluids and their mixtures. 
     
     
         19 . The sensor, as set forth in  claim 16 , wherein the transducer comprises an inductor-capacitor-resistor (LCR) transducer. 
     
     
         20 . The sensor, as set forth in  claim 19 , wherein the LCR transducer comprises an RFID transducer with an integrated circuit chip. 
     
     
         21 . The sensor, as set forth in  claim 19 , wherein the sensor has multiple components of LCR response from the LCR transducer, wherein the multiple components of LCR response originate from one or more factors affecting the LCR transducer. 
     
     
         22 . The sensor, as set forth in  claim 21 , wherein the one or more factors comprise resistance and capacitance of the sensing material, resistance and capacitance between the transducer and the sensing material, and resistance and capacitance between a transducer substrate and the sensing material.