Ion detection using a pillar chip

Abstract

The present invention provides methods and assemblies for ion detection of samples using a chip with elevated sample zones. The elevated sample zones provide a number of ion detection advantages over chips with non-elevated sample zones. Embodiments of the invention have a number of applications in drug discovery, environmental analyses for tracking and the identification of contaminants, target discovery and/or validation as well as in diagnostics in a clinical setting for staging or disease progression. In addition, the invention may also be used with research and clinical microarray systems and devices.

1 . A method comprising: 
 (a) desorbing a sample from a chip to produce a desorbed ion sample, wherein the chip comprises: 
 i. a base having a surface, and  
 ii. one or more structures protruding above the surface of the base, each structure comprising a pillar and a sample zone, wherein the sample zone comprises a support material and the sample;  
   (b) detecting the desorbed ion sample with an ion detector.    
     
     
         2 . The method of  claim 1  further comprising allowing the desorbed ion sample to pass through an aperture in a conductive element, wherein the conductive element comprises a different electrical potential than the base.  
     
     
         3 . The method of  claim 2 , wherein the position of the chip is translatable, wherein the method further comprises aligning the aperture with one of the structures whereby the desorbed ion sample passes through the aperture after (a) but before (b).  
     
     
         4 . The method of  claim 1 , wherein said support material receives radiation.  
     
     
         5 . The method of  claim 1 , wherein each pillar and the base comprise the support material that receives radiation.  
     
     
         6 . The method of  claim 1 , wherein said support material is porous.  
     
     
         7 . The method of  claim 1 , wherein said support material is conducting or semiconducting.  
     
     
         8 . The method of  claim 1 , wherein said support material is capable of transferring energy to the sample after receiving radiation.  
     
     
         9 . The method of  claim 1 , wherein the support material is coated with a surface coating comprising a binding reagent, wherein the binding reagent interacts with the sample.  
     
     
         10 . The method of  claim 9 , wherein the interaction between the binding reagent and the sample is a specific binding event.  
     
     
         11 . The method of  claim 1 , wherein the pillar and sample zone are identical in chemical composition.  
     
     
         12 . The method of  claim 1 , further comprising directing radiation at the sample zone before (a).  
     
     
         13 . The method of  claim 2 , further comprising directing radiation at the sample zone before (a) through a window in the conductive element.  
     
     
         14 . The method of  claim 1 , wherein the ion detector forms part of a mass spectrometer.  
     
     
         15 . An analytical assembly comprising: 
 a. a chip comprising: 
 i. a base having a surface; and  
 ii. one or more structures protruding above the surface of the base, each structure comprising a pillar and a sample zone, wherein the sample zone comprises a support material; and  
   b. a conductive element comprising: 
 i. an aperture of sufficient proportion to allow passage of a molecular ion; and  
 ii. is adapted to be at a different electrical potential than the base.  
   
     
     
         16 . The analytical assembly of  claim 15 , wherein said support material is adapted to receive radiation.  
     
     
         17 . The analytical assembly of  claim 16 , wherein each pillar and the base comprise said support material.  
     
     
         18 . The analytical assembly of  claim 15 , wherein said support material is porous.  
     
     
         19 . The analytical assembly of  claim 15 , wherein said support material is conducting or semi-conducting.  
     
     
         20 . The analytical assembly of  claim 15 , wherein said support material is capable of transferring energy to a sample after receiving radiation.  
     
     
         21 . The analytical assembly of  claim 15 , wherein the position of the chip is translatable, thereby allowing alignment of the aperture with a structure whereby a sample desorbed from the structure and attracted toward the conductive element passes through the aperture.  
     
     
         22 . The analytical assembly of  claim 15 , wherein the sample zone is coated with a surface coating comprising a binding reagent, wherein the binding reagent interacts with a sample.  
     
     
         23 . The analytical assembly of  claim 22 , wherein the interaction between the binding reagent and the sample is a specific binding event.  
     
     
         24 . The analytical assembly of  claim 15 , wherein the pillar and sample zone are identical in chemical composition.  
     
     
         25 . The analytical assembly of  claim 15 , wherein the conductive element further comprises an ion detector.  
     
     
         26 . The analytical assembly of  claim 15 , wherein the conductive element further window, wherein radiation is passed through said window.  
     
     
         27 . A mass spectrometer apparatus comprising: 
 (a) an analytical assembly comprising 
 (i) a chip comprising: 
 A. a base having a surface; and  
 B. one or more structures protruding above the surface of the base, each structure comprising a pillar and a sample zone, wherein the sample zone comprises a support material; and  
 
 (ii) a conductive element comprising: 
 A. an aperture of sufficient proportion to allow passage of a molecular ion; and  
 B. is adapted to be at a different, electrical potential than the base.  
 
   (b) an ionization source to ionize the sample; and    (c) an ion detector for detecting an ion desorbed from the sample zone.