Method and Apparatus for Detecting and Quantifying a Chemical Substance Employing an Optical Transmission Property of Metallic Islands on a Transparent Substrate

Abstract

A sensor for use in detecting and analyzing predetermined chemical substances is presented. The sensor comprises: a first structure configured for binding to a certain substance and comprising a substantially transparent substrate with respect to electromagnetic radiation of a predetermined wavelength range and a plurality of metallic islands deposited onto the transparent substrate and having a first spectral transmission profile with respect to the electromagnetic radiation of the predetermined wavelength range; the metallic islands comprising metallic films having a thickness selected such that binding of said certain substance to the first structure provides a change in a localized surface plasmon extinction in the metallic films being in a predetermined correlation with a change in a spectral transmission profile of the electromagnetic radiation of the predetermined wavelength range transmitted through the first structure and the substance as compared to said first spectral transmission profile, thereby enabling detection of said substance.

1 . A sensor for use in detecting and analyzing at least one predetermined chemical substance comprising:
 a first structure configured for binding to a certain substance, the first structure comprising a substantially transparent substrate with respect to electromagnetic radiation of a predetermined wavelength range and a plurality of metallic islands deposited onto the transparent substrate and having a first spectral transmission profile with respect to the electromagnetic radiation of the predetermined wavelength range;   the metallic islands comprising metallic films having a thickness selected such that binding of said certain substance to the first structure provides a change in a localized surface plasmon extinction in the metallic films being in a predetermined correlation with a change in a spectral transmission profile of the electromagnetic radiation of the predetermined wavelength range transmitted through the first structure and the substance as compared to said first spectral transmission profile, thereby enabling detection of said substance.   
     
     
         2 . The sensor of  claim 1 , wherein the thickness of the metallic film substantially does not exceed 10 nm. 
     
     
         3 . The sensor of  claim 1 , wherein the metallic films are made of Au or Ag. 
     
     
         4 . The sensor of  claim 1 , wherein correlating the change in the plasmon extinction with a change in the spectral transmission profile occurs at a single wavelength λ. 
     
     
         5 . The sensor of  claim 1 , wherein said predetermined wavelength range of the electromagnetic radiation includes UV, infrared or visible radiation. 
     
     
         6 . The sensor of  claim 1 , wherein the first structure further comprises an intermediate layer bound to the metallic islands. 
     
     
         7 . The sensor of  claim 1 , wherein the substance is a chemical or biological substance. 
     
     
         8 . The sensor of  claim 1 , wherein the substance is in a liquid or gaseous form. 
     
     
         9 . The sensor of  claim 1 , wherein said substrate comprises an analyte comprising chemical or biological molecules. 
     
     
         10 . The sensor of  claim 9 , wherein the first structure comprises an intermediate layer bound to the metallic islands, a change in the localized surface plasmon extinction occurring due to adsorption or desorption of the analyte onto said layer. 
     
     
         11 . A sensor comprising:
 a first structure configured for binding to a certain substance, the first structure comprising a substantially transparent substrate with respect to electromagnetic radiation of a predetermined wavelength range and a plurality of metallic islands deposited onto the transparent substrate and having a first spectral transmission profile with respect to the electromagnetic radiation of the predetermined wavelength range;   the metallic islands comprising metallic films and a layer bound to the metallic films, a thickness of the metallic films being selected such that binding of the certain substance to the layer of the first structure causes a change in a localized surface plasmon extinction in the metallic films that can be detected by correlating the change in the localized surface plasmon extinction with a change in a spectral transmission profile of the electromagnetic radiation of the predetermined wavelength range transmitted through the first structure, the layer and the substance as compared to said first spectral transmission profile.   
     
     
         12 . The sensor of  claim 11 , wherein the thickness of the metallic film substantially does not exceed 10 nm. 
     
     
         13 . The sensor of  claim 11 , wherein the metallic films are made of Au or Ag. 
     
     
         14 . The sensor of  claim 11 , wherein correlating the change in the plasmon extinction with a change in the spectral transmission profile occurs at a single wavelength λ. 
     
     
         15 . The method of  claim 11 , wherein the predetermined wavelength range of the electromagnetic radiation includes UV, infrared or visible radiation. 
     
     
         16 . The method of  claim 11 , wherein the layer has specific affinity to the substance. 
     
     
         17 . The method of  claim 11 , wherein the change in the localized surface plasmon extinction correlates with a change in spectral transmission profile of the electromagnetic radiation transmitted through the first structure, the layer and the substance.