Biological fluid sampling and analyte measurement devices and methods

Abstract

A device for sampling a biological fluid and measuring a target analyte within the biological fluid is provided. The device has at least one micro-piercing member used to penetrate the skin to a selected depth and access biological fluid, a sampling means and a measuring means. The sampling means comprises a fluid transfer medium, such as a hydrophilic porous material, by which sampled biological fluid is transferred from the micro-piercing member to the measuring means. The measuring means includes an electrochemical cell having at least one porous electrode and, typically, a reagent material, where the electrochemical cell is configured so as to make an electrochemical measurement of a target analyte in accessed biological fluid present therein. Methods of sampling biological fluids within the skin and measuring the sampled fluids are also provided, as well as kits comprising one or more of the inventive devices.

1 .- 30 . (Cancelled)  
     
     
         31 . An analyte sensor device, comprising: 
 an electrochemical cell comprising at least one porous electrode; and    a fluid transfer medium comprising a more porous proximal portion and a less porous distal portion wherein the more porous proximal portion is externally adjacent the at least one porous electrode.    
     
     
         32 . (Cancelled)  
     
     
         33 . The device of  claim 31  wherein the less porous distal portion comprises a distal surface having at least one skin-piercing micro-protrusions formed thereon.  
     
     
         34 . The device of  claim 33  wherein the distal surface is non-porous.  
     
     
         35 . The device of  claim 31  wherein the electrochemical cell comprises two porous electrodes.  
     
     
         36 .- 56 . (Cancelled)  
     
     
         57 . The device of  claim 31  wherein the electrochemical cell comprises two spaced-apart electrodes defining a reaction chamber and a selected reagent for chemically reacting with an analyte targeted for measurement.  
     
     
         58 . The device of  claim 57  wherein the distance between the electrodes is from about 10 to 300 microns.  
     
     
         59 . (New) The device of claim  8  wherein the distance between the electrodes is from about 10 to 150 microns.  
     
     
         60 . The device according to  claim 57  wherein the reagent is located on a surface of at least one electrode facing the reaction chamber.  
     
     
         61 . The device of  claim 57  wherein both electrodes are porous.  
     
     
         62 . The device of  claim 31  wherein the proximal portion is about 10 to 100 times more porous than the distal portion.  
     
     
         63 . The device of  claim 31  wherein the porous portions comprise pores having diameters in the range from about 0.1 to 50 μm.  
     
     
         64 . The device of  claim 63  wherein the pore diameters are in the range from about 0.1 to 10 μm.  
     
     
         65 . The device of  claim 31  wherein the at least one porous electrode comprises a material selected from the group consisting of polymers, ceramics, glass and silica.  
     
     
         66 . The device of  claim 31  wherein the at least one porous electrode comprises a hydrophilic gel.  
     
     
         67 . The device of  claim 31  further comprising a housing having at least one vent hole for venting air from within the electrochemical cell.