Electrospray apparatus with an integrated electrode

Abstract

The invention provides related apparatus and methods of making an integrated electrospray tip by depositing ionic and/or electronic conductor materials onto a planar substrate. The invention also features methods of forming an electrospray apparatus comprising coupling a first planar substrate to the surface of a second planar substrate, wherein a surface on at least one of the substrates includes one or more microfluidic channels and/or reservoirs which are at least partially or totally enclosed therebetween. The conductive regions of the apparatus do not intersect the microfluidic channels within other portions of the apparatus provided preferably. The invention further provides related apparatus and methods for manufacturing and using microfluidic devices with integrated electrodes for electrospray ionization. The electrospray apparatus in some embodiments may include an electronic conductor electrode or an ionic conductor electrode formed from a microfluidic channel containing a conductive material selected from a variety of solutions and gels.

1 . A method of making an electrospray apparatus comprising: 
 providing a first planar substrate featuring a conductive region; and thereafter    coupling said first planar substrate to a second planar substrate to form a microfluidic channel that is at least partially enclosed therebetween and not intersecting with the conductive region, and wherein at least one of said first and second planar substrates tapers to form an electrospray tip.    
   
   
       2 . A method of making an electrospray apparatus comprising: 
 providing a first planar substrate featuring a conductive region including an electrode formed from an ionic conductor; and thereafter    coupling said first planar substrate to a second planar substrate to form a microfluidic channel that is at least partially enclosed therebetween and non-intersecting with the conductive region, and wherein at least one of said first and second planar substrates tapers to form an electrospray tip.    
   
   
       3 . A method of making an electrospray apparatus comprising: 
 providing a first planar substrate featuring a selected ionic conductor material serving as an electrode; and thereafter    coupling said first planar substrate to a second planar substrate to form one or more microfluidic channels that are at least partially enclosed between the substrates which are not in direct contact with the ionic conductor material, and wherein at least one of said first and second planar substrates tapers to form an electrospray tip.    
   
   
       4 - 101 . (canceled)  
   
   
       102 . An electrospray apparatus comprising: 
 a first planar substrate coupled to a second planar substrate to form at least one microfluidic channel that is at least partially enclosed, and    wherein said first planar substrate includes a conductive region that does not intersect the microfluidic channel; and at least one of said first and second planar substrates tapers to form an electrospray tip.    
   
   
       103 . An electrospray apparatus comprising: 
 a first planar substrate coupled to a second planar substrate to form at least one microfluidic channel that is at least partially enclosed therebetween, and    wherein said first planar substrate having a conductive region that includes a selected ionic conductor serving as an electrode which does not directly contact the microfluidic channel; and at least one of said first and second planar substrates tapers to form an electrospray tip.    
   
   
       104 . An electrospray apparatus comprising: 
 a first planar substrate coupled to a second planar substrate which forms at least a partially enclosed microfluidic channel, and    wherein said first planar substrate contains an ionic conductor electrode that does not intersect any portion of the microfluidic channel; and at least one of said first and second planar substrates tapers to form an electrospray tip.    
   
   
       105 . The electrospray apparatus as recited in  claim 102 ,  103  or  104  wherein at least one of said first and second planar substrates contains another microfluidic channel and/or reservoir.  
   
   
       106 . An electrospray apparatus comprising: 
 a first planar substrate coupled to a second planar substrate, wherein said first planar substrate includes a conductive region and said second planar substrate is coupled to a third planar substrate; and    wherein at least one microfluidic channel which does not intersect the conductive region is formed as between the first and second planar substrates and the second and third planar substrates, and wherein at least one of said second and third planar substrates tapers to form an electrospray tip.    
   
   
       107 . An electrospray apparatus comprising: 
 a first planar substrate coupled to a second planar substrate wherein said first planar substrate having a conductive region; said first planar substrate containing a selected ionic conductor for providing an electrode; said second planar substrate is coupled to a third planar substrate; and at least one of said second and third planar substrates tapers to form an electrospray tip.    
   
   
       108 . An electrospray apparatus comprising: 
 a first planar substrate coupled to a second planar substrate wherein said first planar substrate contains an ionic conductor electrode; said second planar substrate is coupled to a third planar substrate; and at least one of said second and third planar substrates tapers to form an electrospray tip.    
   
   
       109 . The electrospray apparatus as recited in  claim 106 ,  107  or  108  wherein at least one of said second and third planar substrates contains a microfluidic channel and/or reservoir.  
   
   
       110 . The electrospray apparatus as recited in  claim 102 ,  103 ,  106  or  107  wherein said conductive region is made by depositing a conductive material onto a surface of said first planar substrate.  
   
   
       111 . The electrospray apparatus as recited in  claim 102 ,  103 ,  106  or  107  wherein said conductive region is made by adding a conductive component to a surface portion of said first planar substrate.  
   
   
       112 . The electrospray apparatus as recited in  claim 102 ,  103 ,  106  or  107  wherein said conductive region is made by adding a conductive component to an entire surface of said first planar substrate.  
   
   
       113 . The electrospray apparatus as recited in  claim 102 ,  103 ,  106  or  107  wherein said conductive region forms a single trace on said first planar substrate.  
   
   
       114 . The electrospray apparatus as recited in  claim 102 ,  103 ,  106  or  107  wherein said conductive region forms more than two traces on said first planar substrate.  
   
   
       115 . The electrospray apparatus as recited in  claim 104  or  108  wherein a selected portion of said first planar substrate serves as an electrode.  
   
   
       116 . The electrospray apparatus as recited in  claim 104  or  108  wherein a selected portion of said first planar substrate serves as a single electrode.  
   
   
       117 . The electrospray apparatus as recited in  claim 104  or  108  wherein said first planar substrate contains more than a single electrode.  
   
   
       118 . The electrospray apparatus as recited in  claim 102 ,  103 ,  106  or  107  wherein said second planar substrate features a conductive region.  
   
   
       119 . The electrospray apparatus as recited in  claim 104  or  108  wherein said third planar substrate features a conductive region.  
   
   
       120 . The electrospray apparatus as recited in  claim 102 ,  103 ,  106  or  107  wherein said conductive region extends about 10 μm to about 1,000 μm from the edge of said first planar substrate.  
   
   
       121 . The electrospray apparatus as recited in  claim 102 ,  103 ,  106  or  107  wherein said conductive region extends about 40 μm to about 200 μm from the edge of said first planar substrate.  
   
   
       122 . The electrospray apparatus as recited in  claim 102 ,  103 ,  106  or  107  wherein said conductive region extends about 20 μm to about 30 μm from the edge of said first planar substrate.  
   
   
       123 . The electrospray apparatus as recited in  claim 104  or  108  wherein said electrode extends about 10 μm to about 1,000 μm from the edge of said first planar substrate.  
   
   
       124 . The electrospray apparatus as recited in  claim 104  or  108  wherein said electrode extends about 40 μm to about 200 μm from the edge of said first planar substrate.  
   
   
       125 . The electrospray apparatus as recited in  claim 104  or  108  wherein said electrode extends about 20 μm to about 30 μm from the edge of said first planar substrate.  
   
   
       126 - 204 . (canceled)