Solution drying system

Abstract

A system for drying chemical reagents on material, particularly for producing product used in making reagent test strips is described. By drying selected chemicals on substrate drawn past a radiant energy source (preferably an IR source), rapid drying may be achieved while obtaining high-quality product. Airflow sufficient to break or disturb a vapor boundary layer above drying solution may be provided to increase drying speeds. Any airflow provided should not disturb the surface of the solution. Still, air-impingement drying techniques may be employed in the system to finish drying reagent material once it is sufficiently dry to be stable in shape. The substrate upon which chemicals are dried may include a reflective coating to facilitate its use with high levels of radiant energy. A metallic or metalized substrate is advantageously used in producing electrochemical test strips. Such test strips may be used in conjunction with various kits and be conveniently read using known hand-held meters.

That being said, we claim:  
     
         1 . A method of producing reagent coated substrate comprising: 
 coating substrate with reagent in solution, and exposing said solution to radiant energy provided by at least one radiant energy heater.    
     
     
         2 . The method of  claim 1 , wherein airflow sufficient only to break a vapor barrier of the solution is directed at said solution while exposed to radiant energy.  
     
     
         3 . The method of  claim 1 , wherein said substrate is provided in a roll, and is fed past said energy source.  
     
     
         4 . The method of  claim 1 , wherein said reagent is provided in at least one stripe.  
     
     
         5 . The method of  claim 1;  wherein said substrate includes a reflective surface.  
     
     
         6 . The method of  claim 5 , wherein said feeding of said substrate is performed at a rate between about 5 and 50 feet per minute.  
     
     
         7 . The method of  claim 5 , wherein said radiant energy is infrared energy delivered at an intensity of at least 3.5 W/in 2 .  
     
     
         8 . A reagent coated substrate made by the process of  claim 1 , whereby dried reagent having a substantially uniform thickness is produced.  
     
     
         9 . The reagent coated substrate of  claim 8 , wherein said substrate comprises an inert backing material and a metallic coating.  
     
     
         10 . The reagent coated substrate of  claim 8 , in a test strip precursor.  
     
     
         11 . The reagent coated substrate of  claim 8 , in a reagent test strip.  
     
     
         12 . The reagent coated substrate of  claim 8 , in an electrochemical-type test strip.  
     
     
         13 . The reagent coated substrate of  claim 8 , in an electrochemical-type test strip comprising a pair of electrodes and a spacer therebetween defining a reaction zone.  
     
     
         14 . The reagent coated substrate of  claim 8 , in a reagent test strip wherein said reagent test strip can be read by a hand held meter.  
     
     
         15 . A system for use in determining the concentration of an analyte in a physiological sample, comprising: 
 a reagent test strip comprising substrate as described in  claim 8  in combination with a hand-held meter, wherein said reagent test strip and said meter are adapted to interface with one another.    
     
     
         16 . The system of  claim 15 , wherein said reagent test strip is received by said meter.  
     
     
         17 . A kit for use in determining the concentration of an analyte in a physiological sample, comprising: 
 a reagent test strip comprising substrate as described in  claim 8  in packaged combination with at least one of a set of directions for test strip use, a means for obtaining a physiological sample, and an analyte standard.    
     
     
         18 . A method for determining the concentration of an analyte in a sample, said method comprising: 
 applying a fluid sample to a reagent test strip comprising a reagent coated substrate as described in  claim 8;     detecting a signal from said reagent test strip; and    relating said detected signal to the concentration of analyte in said sample to determine the concentration of said analyte in said fluid sample.    
     
     
         19 . The method of  claim 18 , wherein said fluid sample is a biological sample.  
     
     
         20 . The method of  claim 18 , wherein said analyte is glucose.  
     
     
         21 . The method of  claim 18 , wherein said detecting and relating steps are performed by a hand held meter.