Method of making sensor

Abstract

A sensor is provided for the determination of various concentrations of one or more components within a fluid sample. The sensor includes an injection molded body, at least two electrodes, an enzyme, and if desired, an electron transfer mediator. The body includes a reaction zone for receiving a fluid sample. The electrodes are at least partially embedded within the plastic body and extend into the reaction zone. Also contained within the reaction zone is an enzyme capable of catalyzing a reaction involving a compound within the fluid sample. Additionally, the sensor incorporates fill detection which activates a meter, attached to the sensor, for measuring the electrochemical changes occurring in the reaction zone.

1 . A method of making a testing device for testing a fluid sample comprising the steps of: 
 positioning and holding in place at least two spaced apart electrically conductive electrodes in a mold;    molding a body within the mold of insulative material to at least either embed or encase a part of the electrodes in the insulative material and to permit exposure of at least a portion of one electrode to a fluid sample reaction zone by forming a channel with the mold; and,    treating at least one of the electrodes with one or more substances either before or after the molding of the body for reacting with the fluid sample to be tested.    
   
   
       2 . The method of  claim 1  wherein the electrically conductive electrodes are substantially molded into the insulative material with at least a part thereof either embedded within or encased by the insulative material and the electrodes are disposed in fixed longitudinal relation in the insulative material.  
   
   
       3 . The method of  claim 1  wherein the molding step includes forming a hinge in the body for permitting the pivoting and connecting of a portion of the body onto itself.  
   
   
       4 . The method of  claim 1  wherein the molding step comprises molding the body in two pieces, an electrode-encasing housing and an end cap, both of the pieces being hingeably attachable to one another after the molding is completed.  
   
   
       5 . The method of  claim 1  wherein the molding step includes molding into the body a means for receiving the fluid sample.  
   
   
       6 . The method of  claim 8  wherein the means for receiving the fluid sample includes a capillary inlet in the body in communication with a reaction zone and a vent.  
   
   
       7 . The method of  claim 1  wherein the molding step includes forming a vent in the body for detecting when the sensor contains a sufficient quantity of fluid sample for testing.  
   
   
       8 . The method of  claim 1  wherein the molding step includes molding into the body a means for detecting the presence of an adequate amount of sample.  
   
   
       9 . A method of making an electrochemical device for cooperating with a meter to measure electrical properties between at least two electrically conductive electrodes, comprising the steps of: 
 positioning and holding in place at least two spaced apart electrically conductive electrodes in a mold;    molding a body within the mold of insulative material to at least either embed or encase a portion of the electrodes in the insulative material and to permit exposure of at least a portion of one electrode to a fluid sample to be tested; and,    depositing one or more substances on at least one of the electrodes either before or after the molding of the body to react with the fluid sample to be tested and to change the electrical properties between the electrodes.    
   
   
       10 . The method of  claim 9  wherein the electrically conductive electrodes are substantially molded into the insulative material with at least a part thereof either embedded within or encased by the insulative material and the electrodes are disposed in fixed longitudinal relation in the insulative material.  
   
   
       11 . A method of making a testing device for testing a fluid sample comprising the steps of: 
 positioning and holding in place at least two spaced apart electrically conductive electrodes in a mold; and,    molding a body within the mold of insulative material to at least either embed or encase a part of the electrodes in the insulative material and to permit exposure of at least a portion of one electrode to a fluid sample reaction zone by forming a channel with the mold, the molding step forming a hinge in the body for permitting the pivoting and connecting of a portion of the body onto itself.    
   
   
       12 . The method of  claim 11  wherein the electrodes are held in place during the molding step by fingers passing through apertures formed in the body.  
   
   
       13 . The method of  claim 11  further comprising severing a connecting segment via an aperture formed in the body, the connecting segment electrically connecting the at least two spaced apart electrically conductive electrodes prior to severing the connecting segment.  
   
   
       14 . A method of making a testing device for testing a fluid sample, comprising the steps of: 
 positioning a first electrode and a second electrode in a mold;    molding a body of insulative material within the mold to either embed or encase a first portion of the first electrode and a first portion of the second electrode in the insulative material and to permit exposure of a second portion of the first electrode and a second portion of the second electrode; and,    holding the first electrode and the second electrode in place during the molding step using one or more projections passing through the body.