Method and device for sampling and analyzing interstitial fluid and whole blood samples

Abstract

The invention disclosed in this application is a method and device for combining the sampling and analyzing of sub-dermal fluid samples, e.g., interstitial fluid or whole blood, in a device suitable for hospital bedside and home use. It is applicable to any analyte that exists in a usefully representative concentration in the fluid, and is especially suited to the monitoring of glucose.

1 . A fluid sampling device comprising: 
 a body including: 
 a penetration probe having a penetrating end and a communicating end; and  
 an analysis chamber having a volume;  
   a releasable actuator adapted to receive the body, wherein the releasable actuator is capable of supplying a force sufficient to cause the penetration probe to penetrate a dermal layer of a user's skin; and    a pressure sensor, the pressure sensor providing an indication that the penetration probe has penetrated the user's skin.    
     
     
         2 . The fluid sampling device of  claim 1 , wherein the penetration probe is in fluid communication with the analysis chamber such that fluid can flow from the penetration probe toward the analysis chamber.  
     
     
         3 . The fluid sampling device of  claim 1 , wherein the fluid sampling device is adapted to limit the penetration of the penetrating end into the dermal layer to a depth of less than approximately 2 mm.  
     
     
         4 . The fluid sampling device of  claim 1 , wherein the pressure sensor provides an indication that sufficient pressure has been applied to obtain a sample.  
     
     
         5 . The fluid sampling device of  claim 1 , further comprising an interface for communication with a meter.  
     
     
         6 . A fluid sampling system comprising: 
 a meter; and    a fluid sampling device, the fluid sampling device comprising: 
 an interface for communicating with the meter;  
 a body, the body including a dermal layer penetration probe having a penetrating end and a communicating end, the penetration probe having a volume; and  
 an analysis chamber having a proximal and distal end, the analysis chamber having a volume.  
   
     
     
         7 . The fluid sampling system of  claim 6 , wherein the penetration probe is in fluid communication with the analysis chamber such that fluid can flow from the penetration chamber toward the analysis chamber.  
     
     
         8 . The fluid sampling system of  claim 6 , wherein the penetration probe is capable of exerting a first capillary force and the analysis chamber is capable of exerting a second capillary force, and wherein a differential in capillary force exists between the first capillary force and the second capillary force.  
     
     
         9 . The fluid sampling system of  claim 6 , wherein the fluid sampling device further comprises a pre-chamber having a volume and a first and second end, the pre-chamber interposed between the penetration probe and the analysis chamber such that the first end of the pre-chamber is adjacent the communicating end of the penetration probe and the second end of the pre-chamber is adjacent the proximal end of the analysis chamber.  
     
     
         10 . The fluid sampling system of  claim 6 , wherein the volume of the pre-chamber is greater than the volume of the analysis chamber.  
     
     
         11 . The fluid sampling system of  claim 6 , wherein the analysis chamber has at least one flexible wall and wherein upon compression of the chamber at the flexible wall the volume of the analysis chamber is reduced.  
     
     
         12 . The fluid sampling system of  claim 6 , wherein the pre-chamber has at least one flexible wall and wherein upon compression of the pre-chamber at the flexible wall the volume of the pre-chamber is reduced.  
     
     
         13 . The fluid sampling device of  claim 6 , wherein the fluid sampling device is adapted to limit the penetration of the penetrating end into the dermal layer to a depth of less than approximately 2 mm.  
     
     
         14 . The fluid sampling system of  claim 6 , wherein the analysis chamber comprises an electrochemical cell, the cell comprising a working electrode and a counter/reference electrode.  
     
     
         15 . The fluid sampling system of  claim 6 , wherein the meter is configured to display, store, or record test data.  
     
     
         16 . A fluid sampling system comprising: 
 a meter; and    a fluid sampling device, the fluid sampling device comprising: 
 an interface for communicating with a meter;  
 a body including: 
 a penetration probe having a penetrating end and a communicating end;  
 an analysis chamber having a volume; and  
 a releasable actuator adapted to receive the test strip, wherein the releasable actuator is capable of supplying a force sufficient to cause the penetration probe to penetrate a dermal layer of a user's skin; and  
 
 a pressure sensor, the pressure sensor providing an indication that the penetration probe has penetrated the user's skin.  
   
     
     
         17 . The fluid sampling system of  claim 16 , wherein the pressure sensor additionally provides an indication that sufficient pressure has been applied to obtain a sample.  
     
     
         18 . The fluid sampling system of  claim 16 , wherein the penetration probe is in fluid communication with the analysis chamber such that fluid can flow from the penetration chamber toward the analysis chamber.  
     
     
         19 . The fluid sampling system of  claim 16 , wherein the fluid sampling device further comprises a pre-chamber having a volume and a first and second end, the pre-chamber being interposed between the penetration probe and the analysis chamber such that the first end of the pre-chamber is adjacent the communicating end of the penetration probe and the second end of the pre-chamber is adjacent the proximal end of the analysis chamber.  
     
     
         20 . The fluid sampling system of  claim 16 , wherein the volume of the pre-chamber is greater than the volume of the analysis chamber.  
     
     
         21 . The fluid sampling system of  claim 16 , wherein the analysis chamber has at least one flexible wall and wherein upon compression of the chamber at the flexible wall the volume of the analysis chamber is reduced.  
     
     
         22 . The fluid sampling system of  claim 16 , wherein the pre-chamber has at least one flexible wall and wherein upon compression of the pre-chamber at the flexible wall the volume of the pre-chamber is reduced.  
     
     
         23 . The fluid sampling device of  claim 16 , wherein the fluid sampling device is adapted to limit the penetration of the penetrating end into the dermal layer to a depth of less than approximately 2 mm.  
     
     
         24 . The fluid sampling system of  claim 16 , wherein the analysis chamber comprises an electrochemical cell, the cell comprising a working electrode and a counter/reference electrode.  
     
     
         25 . The fluid sampling system of  claim 16 , wherein the meter is configured to display, store, or record test data.