Microfluidic diagnostic device

Abstract

A method of making a microfluidic diagnostic device for use in the assaying of biological fluids, whereby a layer of adhesive in a channel pattern is printed onto a surface of a base sheet and a cover sheet is adhered to the base sheet with the adhesive. The layer of adhesive defines at least one channel, wherein the channel passes through the thickness of the adhesive layer.

What is claimed is: 
     
         1 . A method of making a microfluidic diagnostic device, the method comprising:
 applying at least one adhesive layer in a pattern onto a surface of a base sheet, wherein the pattern defines at least one valley having a mean width less than 1.0 mm; and   adhering a cover sheet directly onto the at least one adhesive layer to enclose the at least one valley.   
     
     
         2 . The method of  claim 1  wherein applying occurs by printing. 
     
     
         3 . The method of  claim 2  wherein printing occurs by at least one of: screen printing, pad printing, transfer printing and spray printing. 
     
     
         4 . The method of  claim 1  further comprising polymerizing the at least one adhesive layer. 
     
     
         5 . The method of  claim 4  wherein polymerizing occurs subsequent to adhering the cover sheet to the at least one adhesive layer. 
     
     
         6 . The method of  claim 5  wherein polymerizing occurs by exposing the at least one adhesive layer to at least one of: ultraviolet radiation, gamma radiation and heat. 
     
     
         7 . The method of  claim 1  further comprising applying at least one additional adhesive layer to the at least one adhesive layer. 
     
     
         8 . A method of making a microfluidic diagnostic device, the method comprising:
 applying at least one layer of an adhesive in a channel pattern onto a surface of a base sheet, wherein the pattern defines at least one channel passing through a thickness of the adhesive; and   attaching a cover sheet to the base sheet with the adhesive to enclose the at least one channel, wherein either the base sheet or the cover sheet or both comprise a non-hydrophilic surface in contact with the at least one channel.   
     
     
         9 . The method of  claim 8  wherein applying occurs by printing. 
     
     
         10 . The method of  claim 9  wherein printing is accomplished by at least one of: screen printing, pad printing, transfer printing and spray printing. 
     
     
         11 . The method of  claim 8  further comprising the act of curing the adhesive. 
     
     
         12 . The method of  claim 11  wherein curing occurs subsequent to attaching the cover sheet to the base sheet. 
     
     
         13 . The method of  claim 11  wherein curing is accomplished by exposing the adhesive to at least one of: ultraviolet radiation, gamma radiation, heat and pressure. 
     
     
         14 . The method of  claim 8  further comprising the act of applying at least one additional layer of adhesive to the at least one layer of adhesive. 
     
     
         15 . A microfluidic diagnostic device adapted for use in the assaying of biological fluids, the device comprising:
 a base sheet;   one or more adhesive layers disposed on the base sheet in a pattern, wherein the one or more adhesive layers define at least one fluid transport channel having a mean width less than 1.0 mm;   at least one fluid sample inlet portal in fluid communication with the at least one fluid transport channel;   at least one vent aperture configured to be in fluid communication with the at least one fluid transport channel; and   a cover sheet placed directly on an adhesive layer, the cover sheet being adhered to the base sheet by the one or more adhesive layers.   
     
     
         16 . The device of  claim 15  wherein at least one of the base sheet and the cover sheet comprise a hydrophilic surface. 
     
     
         17 . The device of  claim 15  wherein the one or more adhesive layers define a plurality of channels and wherein adjacent channels are separated by adhesive and by non-channel space that is void of adhesive. 
     
     
         18 . The device of  claim 15  wherein the adhesive is non-hydrophilic. 
     
     
         19 . The device of  claim 15  wherein the adhesive is a solvent-based adhesive. 
     
     
         20 . The device of  claim 15  wherein the adhesive is UV curable.