Device For Moving Magnetic Nanoparticles Through Tissue

Abstract

The movement of magnetically responsive nanoparticles through a membrane is significantly enhanced by varying the direction of the magnetic field gradient at the membrane. A device for generating the varying-gradient magnetic field includes a primary magnet having a primary magnetic field gradient direction, one or more secondary magnets directed at an acute angle relative to the primary magnetic field gradient direction, and a controller connected to at least the secondary magnets. The controller is operable to repetitively vary the direction of the resultant magnetic field gradient in a pulsating manner.

1 . A device for generating a varying-gradient magnetic field for moving magnetically responsive nanoparticles through a membrane, the device comprising:
 a primary magnet having a primary magnetic field gradient direction;   one or more secondary magnets directed at an acute angle relative to the primary magnetic field gradient direction; and   a controller connected to at least the secondary magnets and operable to repetitively vary the direction of the resultant magnetic field gradient at the membrane in a pulsating manner.   
     
     
         2 . The device of  claim 1  further comprising a positioning means for positioning the one or more magnets proximate the membrane. 
     
     
         3 . The device of  claim 1 , wherein at least one of the secondary magnets is an electromagnet connectable to a power source. 
     
     
         4 . The device of  claim 3  wherein the controller comprises an electrical switch for oscillating power to the at least one electromagnet. 
     
     
         5 . The device of  claim 3  wherein the controller is adapted to oscillate the magnetic field intensity on and off. 
     
     
         6 . The device of  claim 1  comprising two secondary electromagnets. 
     
     
         7 . The device of  claim 6  wherein the primary magnet is a permanent magnet. 
     
     
         8 . The device of  claim 6  wherein the primary magnet is an electromagnet. 
     
     
         9 . The device of  claim 6  wherein the controller is adapted to alternately pulse the two secondary electromagnets.