Magnetically controlled permeability membranes

Abstract

A bioactive material delivery system can include a thermoresponsive polymer membrane and nanowires distributed within the thermoresponsive polymer membrane. Magnetic activation of a thermoresponsive polymer membrane can take place via altering the magnetization or dimensions of nanowires dispersed or ordered within the membrane matrix.

1 - 10 . (canceled) 
     
     
         11 . A method of making a delivery device comprising:
 forming a thermoresponsive polymer membrane in contact with the plurality of nanowires whereby permeability of the thermoresponsive polymer membrane is altered by exposure to a magnetic field such that a bioactive passes through the membrane in the altered condition and not in the unaltered condition.   
     
     
         12 . The method of  claim 11 , wherein forming the membrane includes mixing the thermoresponsive polymer with the plurality of nanowires and casting the membrane. 
     
     
         13 . The method of  claim 11 , further comprising growing a plurality of nanowires on a substrate. 
     
     
         14 . The method of  claim 13 , further comprising depositing the thermoresponsive polymer on the substrate. 
     
     
         15 . The method of  claim 11 , further comprising cross-linking the thermoresponsive polymer. 
     
     
         16 . The method of  claim 11 , further comprising contacting the thermoresponsive membrane with a structure configured to contain the bioactive material and pumping mechanism. 
     
     
         17 . A method of delivering a bioactive material comprising:
 administering a delivery device including a thermoresponsive polymer membrane including plurality of nanowires, whereby permeability of the thermoresponsive polymer membrane is altered in the presence of the magnetic field such that a bioactive material passes through the membrane in the altered condition and not in the unaltered condition, to a patient; and   applying the magnetic field to the portion of the delivery device, and   releasing the bioactive material to the patient.   
     
     
         18 . The method of  claim 17 , wherein applying the magnetic field includes subjecting the thermoresponsive polymer membrane to a magnetic field strength effective to alter porosity to the thermoresponsive polymer membrane, wherein the thermoresponsive polymer membrane is substantial non-porous to a bioactive material prior to applying the magnetic field and the thermoresponsive polymer membrane is substantially porous to the bioactive material when the magnetic field is applied to the membrane, and passing a bioactive material through the membrane to the patient. 
     
     
         19 . The method of  claim 17 , further comprising introducing the device to the patient. 
     
     
         20 . The method of  claim 17 , wherein applying the magnetic field increases the average pore size in the thermoresponsive polymer membrane. 
     
     
         21 . The method of  claim 17 , wherein applying the magnetic field includes generating the magnetive field inside the patient. 
     
     
         22 . The method of  claim 17 , wherein applying the magnetic field includes generating the magnetive field external to the patient.