Electrokinetic pump designs and drug delivery systems

Abstract

The present invention provides a fluid delivery system having a first chamber, a second chamber and a third chamber; a flow-through pump element separating the first chamber from the second chamber; a moveable pump element separating the second chamber from the third chamber; a first outlet in communication with the third chamber; and second outlet in communication with the second chamber. Additionally, the present invention provides methods of operating a fluid delivery system having a first chamber, a second chamber and a delivery chamber by reducing the volume of the second chamber while increasing the volume of the delivery chamber without operation of a flow-through pump element that separates the second chamber from the first chamber.

What is claimed is:  
     
         1 . A fluid delivery system, comprising:
 a housing including a first chamber and a second chamber;   a third chamber fluidically separated from the second chamber; and   a flow-through electrokinetic engine in the housing between the first and second chamber;   wherein the first chamber, the second chamber, the third chamber, and the electrokinetic engine are axially aligned; and   wherein, in operation, the fluid delivery system is configured to pump a pump fluid through the flow-through electrokinetic engine only in a single direction from the first chamber to the second chamber when a voltage is applied across the electrodes, the pumping of pump fluid from the first chamber to the second chamber causing a delivery fluid to be delivered from the third chamber.   
     
     
         2 . The fluid delivery system of  claim 1 , wherein the housing further includes the third chamber. 
     
     
         3 . The fluid delivery system of  claim 1 , further comprising a movable member fluidically separating the second chamber from the third chamber, wherein the movable member is configured to pump a delivery fluid from the third chamber when pump fluid is pumped from the first chamber to the second chamber. 
     
     
         4 . The fluid delivery system of  claim 1 , wherein the flow-through electrokinetic engine comprises a pair of capacitive electrodes, each of the capacitive electrodes configured such that a pump fluid can flow therethrough and a porous dielectric material between the electrodes. 
     
     
         5 . The fluid delivery system of  claim 4 , wherein each of the electrodes of the pair of electrodes comprises a material having a capacitance of at least 10 −4  Farads per square centimeter. 
     
     
         6 . The fluid delivery system of  claim 4 , wherein the electrodes comprise a carbon nanofoam. 
     
     
         7 . The fluid delivery system of  claim 4 , wherein the porous dielectric material comprises a microporous filter having a pore size between 100 and 200 nanometers. 
     
     
         8 . The fluid delivery system of  claim 1 , wherein the delivery fluid is a drug, a pharmacological agent, or a therapeutic agent. 
     
     
         9 . The fluid delivery system of  claim 1 , further comprising control circuitry configured to regulate the flow rate and delivery timing of the delivery fluid from the third chamber. 
     
     
         10 . The fluid delivery system of  claim 1 , further comprising a user interface configured to allow a user to provide instructions regarding delivery of the delivery fluid from the third chamber. 
     
     
         11 . The fluid delivery system of  claim 1 , wherein the housing comprises an adhesive configured to attach the housing to skin. 
     
     
         12 . The fluid delivery system of  claim 1 , wherein at least a portion of the housing is shaped to conform to a body contour. 
     
     
         13 . The fluid delivery system of  claim 1 , wherein the housing is flexible so as to conform anatomically to a body contour. 
     
     
         14 . A method of delivering fluid comprising:
 applying a current from a power supply to move a liquid in an electrokinetic device only in a single direction from a first chamber to a second chamber, the liquid flowing axially through a first capacitive electrode, through a porous dielectric, and through a second capacitive electrode to generate electrokinetic power; and   using the generated electrokinetic power to continuously deliver a delivery fluid from a third chamber that is coaxial with the first chamber and the second chamber.   
     
     
         15 . The method of  claim 14 , wherein the first, second, and third chambers are all within a single housing. 
     
     
         16 . The method of  claim 14 , wherein the delivery fluid is a drug, a pharmacological agent, or a therapeutic agent. 
     
     
         17 . The method of  claim 14 , wherein applying a current from a power supply comprises applying current from a battery. 
     
     
         18 . The method of  claim 14 , further comprising regulating the flow rate or the delivery timing of the delivery fluid from the third chamber. 
     
     
         19 . The method of  claim 14 , further comprising obtaining a syringe prefilled with delivery fluid and filling the third chamber with the delivery fluid. 
     
     
         20 . The method of  claim 19 , wherein the syringe is prefilled with a prescribed amount of the delivery fluid.