Medical devices and methods

Abstract

Methods and devices to monitor an analyte in body fluid are provided. Embodiments include continuous or discrete acquisition of analyte related data from a transcutaneously positioned in vivo analyte sensor automatically or upon request from a user. The in vivo analyte sensor is coupled to an electronics unit holding a memory with instruction to cause processing circuitry to initiate a predetermined time period that is longer than a predetermined life of the sensor, during the predetermined time period, convert signals from the sensor related to glucose to respective corresponding glucose levels, without relying on any post-manufacture independent analyte measurements from a reference device, and at the expiration of the predetermined time period, disable, deactivate, or cease use of one or more feature.

What is claimed is: 
     
         1 . A glucose monitoring system, comprising:
 an electrochemical transcutaneous glucose sensor including:
 a distal portion configured to be inserted through a skin surface of a user, such that at least a part of the distal portion is in contact with an interstitial fluid under the skin surface, the distal portion including a working electrode and a counter/reference electrode, and 
 a proximal portion configured to extend above the skin surface after insertion of the distal portion, the proximal portion including a working-electrode contact electrically coupled to the working electrode and a counter/reference-electrode contact electrically coupled to the counter/reference electrode; and 
   an on-body electronics unit including:
 a housing, 
 a printed circuit board comprising first and second dielectric layers, a bottom surface, and a top surface, wherein the bottom surface is electrically coupled to the working-electrode contact with a first applied conductive material comprising silver and the bottom surface is electrically coupled to the counter/reference-electrode contact with a second applied conductive material comprising silver, and wherein the first applied conductive material is spaced apart from the second applied conductive material, 
 an application-specific integrated circuit (ASIC) disposed on the top surface of the printed circuit board and spaced from an outer periphery of the printed circuit board, 
 a loop antenna disposed between the first dielectric layer of the printed circuit board and the second dielectric layer of the printed circuit board and between the top surface of the printed circuit board and the bottom surface of the printed circuit board, 
 a first temperature sensor disposed on the top surface of the printed circuit board, 
 a second temperature sensor disposed on the bottom surface of the printed circuit board, and 
 a battery secured to the printed circuit board by a battery contact terminal; 
   wherein a first portion of the loop antenna is provided around only a portion of the outer periphery of the printed circuit board, and a second portion of the loop antenna is provided across a portion of the printed circuit board and into electrical communication with the ASIC.   
     
     
         2 . The glucose monitoring system of  claim 1 , wherein at least one of the first temperature sensor and the second temperature sensor generates detected temperature data. 
     
     
         3 . The glucose monitoring system of  claim 2 , wherein the detected temperature data is used to process signals from the electrochemical transcutaneous glucose sensor. 
     
     
         4 . The glucose monitoring system of  claim 2 , wherein the detected temperature data is stored in a memory. 
     
     
         5 . The glucose monitoring system of  claim 1 , wherein the proximal portion of the electrochemical transcutaneous glucose sensor is at least partially encapsulated with a potting material. 
     
     
         6 . The glucose monitoring system of  claim 5 , wherein the proximal portion of the electrochemical transcutaneous glucose sensor is entirely encapsulated with the potting material. 
     
     
         7 . The glucose monitoring system of  claim 5 , wherein the potting material comprises polyurethane. 
     
     
         8 . The glucose monitoring system of  claim 1 , wherein the conductive material comprises solder. 
     
     
         9 . The glucose monitoring system of  claim 1 , wherein the housing of the on-body electronics unit has a maximum thickness less than or equal to 5 mm and a maximum diameter less than or equal to 30 mm. 
     
     
         10 . The glucose monitoring system of  claim 1 , further comprising an adhesive layer attached to the housing to form an on-body electronics unit-adhesive layer assembly, and configured to attach to the skin surface of the user. 
     
     
         11 . The glucose monitoring system of  claim 10 , wherein the adhesive layer has a maximum diameter less than or equal to 40 mm. 
     
     
         12 . The glucose monitoring system of  claim 1 , wherein the on-body electronics unit further comprises:
 one or more non-transitory computer-readable mediums comprising instructions which, when executed by processing circuitry, are configured to cause the processing circuitry to:
 initiate a predetermined time period that is longer than a predetermined life of the electrochemical transcutaneous glucose sensor; 
 during the predetermined time period, convert signals from the electrochemical transcutaneous glucose sensor related to glucose to respective corresponding glucose levels without relying on any post-manufacture independent analyte measurements from a reference device; and 
 at the expiration of the predetermined time period, disable, deactivate, or cease use of one or more operational features. 
   
     
     
         13 . The glucose monitoring system of  claim 12 , wherein the predetermined life of the electrochemical transcutaneous glucose sensor is about 10 days. 
     
     
         14 . The glucose monitoring system of  claim 1 , wherein a position of the electrochemical analyte sensor is fixed relative the printed circuit board prior to use and during use. 
     
     
         15 . The glucose monitoring system of  claim 1 , wherein the first applied conductive material comprising silver and the second applied conductive material comprising silver comprise the same material. 
     
     
         16 . A method of manufacturing a glucose monitoring system, including:
 providing an electrochemical transcutaneous glucose sensor including:
 a distal portion configured to be inserted through a skin surface of a user, such that at least a part of the distal portion is in contact with an interstitial fluid under the skin surface, the distal portion including a working electrode and a counter/reference electrode and 
 a proximal portion configured to extend above the skin surface after insertion of the distal portion, the proximal portion including a working-electrode contact electrically coupled to the working electrode and a counter/reference-electrode contact electrically coupled to the counter/reference electrode; 
   providing an on-body electronics unit including:
 a housing; 
 a printed circuit board comprising first and second dielectric layers, a bottom surface, and a top surface, 
 an application-specific integrated circuit (ASIC) disposed on the top surface of the printed circuit board and spaced from an outer periphery of the printed circuit board, 
 a loop antenna disposed between the first dielectric layer of the printed circuit board and the second dielectric layer of the printed circuit board and between the top surface of the printed circuit board and the bottom surface of the printed circuit board, wherein a first portion of the loop antenna is provided around only a portion of the outer periphery of the printed circuit board, a second portion of the loop antenna is provided across a portion of the printed circuit board into electrical communication with the ASIC 
 a first temperature sensor disposed on the top surface of the printed circuit board, 
 a second temperature sensor disposed on the bottom surface of the printed circuit board, and 
 a battery secured to the printed circuit board by a battery contact terminal; 
   integrating the electrochemical transcutaneous glucose sensor and the on-body electronics unit, including:
 electrically coupling the bottom surface of the printed circuit board to the working-electrode contact with a first applied conductive material comprising silver; 
 electrically coupling the bottom surface of the printed circuit board to the counter/reference-electrode contact with a second applied conductive material comprising silver; and 
   at least partially encapsulating the proximal portion of the electrochemical transcutaneous glucose sensor with a potting material.   
     
     
         17 . The method of  claim 16 , further comprising fully encapsulating the proximal portion of the electrochemical transcutaneous glucose sensor with the potting material. 
     
     
         18 . The method of  claim 16 , wherein the potting material comprises polyurethane. 
     
     
         19 . The method of  claim 16 , wherein the conductive material comprises solder. 
     
     
         20 . The method of  claim 16 , wherein the housing of the on-body electronics unit has a maximum thickness less than or equal to 5 mm and a maximum diameter less than or equal to 30 mm. 
     
     
         21 . The method of  claim 16 , further comprising attaching an adhesive layer to the housing to form an on-body electronics unit-adhesive layer assembly. 
     
     
         22 . The method of  claim 21 , wherein the adhesive layer has a maximum diameter less than or equal to 40 mm. 
     
     
         23 . The method of  claim 16 , further comprising providing a sensor delivery unit having an interior compartment, and pre-loading the electrochemical transcutaneous glucose sensor and on-body electronics unit into the interior compartment of the sensor delivery unit. 
     
     
         24 . The method of  claim 16 , wherein the first applied conductive material comprising silver and the second applied conductive material comprising silver comprise the same material.