Communication system with partial power source

Abstract

The system of the present invention includes a conductive element, an electronic component, and a partial power source in the form of dissimilar materials. Upon contact with a conducting fluid, a voltage potential is created and the power source is completed, which activates the system. The electronic component controls the conductance between the dissimilar materials to produce a unique current signature. The system can be used in a variety of different applications, including as components of ingestible identifiers, such as may be found in ingestible event markers, e.g., pharma-informatics enabled pharmaceutical compositions.

What is claimed is: 
     
         1 . A composition comprising:
 an ingestible component comprising an ingestible event marker and a pharmaceutically acceptable carrier; and   an external layer enclosing the ingestible component to provide a protective barrier for the ingestible component, wherein at least a portion of the external layer is configured to dissolve when the external layer is in contact with a liquid;   wherein the ingestible event marker comprises: 
 a control device; and 
 a partial power source comprising first and second electrodes formed of dissimilar electrochemical materials configured to contact an electrically conductive fluid and generate a voltage to energize the ingestible event marker; and 
   wherein the energized ingestible event marker is configured to produce a conductive current flow through the electrically conductive fluid; and   wherein the control device is configured to control the conductive current flow.   
     
     
         2 . The composition according to  claim 1 , wherein the external layer comprises a homogeneous layer of a single material. 
     
     
         3 . The composition according to  claim 1 , wherein the external layer comprises two or more distinct materials. 
     
     
         4 . The composition according to  claim 3 , wherein the two or more distinct materials are present as a multilayer structure. 
     
     
         5 . The composition according to  claim 1 , wherein the external layer is configured to provide aqueous liquid passage through the external layer upon contact of the composition with an aqueous liquid. 
     
     
         6 . The composition according to  claim 1 , wherein the external layer is configured to protect the ingestible component in a dicing process. 
     
     
         7 . The composition according to  claim 1 , wherein the external layer is configured to dissolve in five or more minutes upon being in contact with the liquid. 
     
     
         8 . The composition according to  claim 1 , wherein the external layer is environmentally sensitive. 
     
     
         9 . The composition according to  claim 8 , wherein the external layer is temperature sensitive. 
     
     
         10 . The composition according to  claim 8 , wherein the external layer is pH sensitive.