Methods and devices for localizing compositions

Abstract

Methods for localizing a composition to a treatment site, which includes placing at least two electrodes against a skin surface where dissipation of the composition is to be limited, wherein the at least two electrodes do not penetrate the skin surface; subcutaneously or intramuscularly injecting the composition, which has a net negative or net positive charge at physiological pH, between the at least two electrodes or underneath one of the at least two electrodes; and applying a positive charge to one of the at least two electrodes and a negative charge to another of the at least two electrodes to produce a directional electric field that limits dissipation of the injected composition.

What is claimed is: 
     
         1 . A method for localizing a composition to a treatment site, the method comprising:
 a) placing at least two electrodes against a skin surface where dissipation of the composition is to be limited, wherein the at least two electrodes do not penetrate the skin surface;   b) subcutaneously or intramuscularly injecting the composition between the at least two electrodes or underneath one of the at least two electrodes, wherein the composition comprises a net negative or net positive charge at physiological pH; and   c) applying a positive charge to one of the at least two electrodes and a negative charge to another of the at least two electrodes to produce a directional electric field that limits dissipation of the injected composition.   
     
     
         2 . The method of  claim 1 , wherein the composition comprises a neurotoxin. 
     
     
         3 . The method of  claim 2 , wherein the neurotoxin comprises a Clostridial toxin. 
     
     
         4 . The method of  claim 3 , wherein the neurotoxin comprises a native botulinum toxin. 
     
     
         5 . The method of  claim 4 , wherein the botulinum toxin is selected from the group consisting of a native BoNT/A, a native BoNT/E, and a native BoNT/B. 
     
     
         6 . The method of  claim 2 , wherein the neurotoxin comprises a recombinant botulinum toxin. 
     
     
         7 . The method of  claim 6 , wherein the recombinant botulinum toxin is selected from the group consisting of a recombinant BoNT/A, a recombinant BoNT/E, and a recombinant BoNT/B. 
     
     
         8 . The method of  claim 1 , wherein the composition is injected under the electrode having an opposite charge as the composition. 
     
     
         9 . The method of  claim 1 , wherein the positive and negative charges are applied before and after the step of injecting the composition. 
     
     
         10 . The method of  claim 1 , wherein the positive and negative charges are applied only after the step of injecting the composition. 
     
     
         11 . The method of  claim 1 , wherein the electric field is produced for at least 30 minutes. 
     
     
         12 . The method of  claim 11 , wherein the electric field is produced for at least 45 minutes. 
     
     
         13 . The method of  claim 12 , wherein said electric field is produced for at least 60 minutes. 
     
     
         14 . The method of  claim 1 , wherein the step of applying positive and negative charges comprises applying a direct current or a pulsed current.