Method of performing array-based hybridization assays using thermal inkjet deposition of sample fluids

Abstract

Methods are provided for depositing a quantity of fluid onto the surface of an array. In the subject methods, a thermal inkjet head loaded with the fluid is positioned in opposing relationship to, e.g. over, the array surface. Actuation of the thermal ink-jet results in the expulsion of a quantity of fluid onto the array surface. The subject methods find particular use in array-based binding assays in which an array of binding agents is employed for the detection of an analyte(s), particularly array-based hybridization assays.

1 - 21 . (canceled)  
     
     
         22 . A method for screening a fluid sample at least suspected of containing an analyte, comprising: 
 positioning an inkjet head filled with a fluid in opposing relation to an array surface comprising a plurality of binding agents stably associated therewith; and    actuating the inkjet head in a manner sufficient to expel said fluid onto a location on the array substrate comprising a binding agent;    detecting a specific binding interaction between the binding agent and an analyte in said fluid.    
     
     
         23 . The method of  claim 22  further comprising depositing a diluent solution onto the array surface at the same location that the fluid sample is deposited.  
     
     
         24 . The method of  claim 22 , further comprising filling the inkjet head with a wash fluid and depositing said wash fluid on said surface.  
     
     
         25 . The method of  claim 22 , wherein the fluid sample comprises a biomolecule.  
     
     
         26 . The method of  claim 22 , wherein the fluid sample comprises a nucleic acid.  
     
     
         27 . The method of  claim 22 , wherein the fluid sample comprises a polypeptide.  
     
     
         28 . The method of  claim 22 , wherein the fluid sample comprises a cell.  
     
     
         29 . The method of  claim 22 , wherein the fluid sample is heated prior to being expelled.  
     
     
         30 . The method according to  claim 22 , wherein said fluid sample does not exceed 200 picoliters in volume.  
     
     
         31 . The method of  claim 22 , wherein said positioning and actuating steps are performed at each of a plurality of locations on the array.