Composition and method for inhibiting uptake of biguanide antimicrobials by hydrogels

Abstract

The invention provides a method for inhibiting the binding of a biguanide antimicrobial in aqueous solution to a hydrogel in contact with said solution comprising providing in said solution an amount of cyclodextrin sufficient to inhibit sorption of the biguanide antimicrobial to a hydrogel.

What is claimed:  
     
         1 . A method for inhibiting the binding of a biguanide antimicrobial in aqueous solution to a hydrogel in contact with said solution comprising providing in said solution an amount of cyclodextrin sufficient to inhibit binding of the biguanide antimicrobial to the hydrogel.  
     
     
         2 . The method of  claim 1  wherein the biguanide antimicrobial is selected from the group consisting of poly(hexamethylene) biguanide and alexidine.  
     
     
         3 . The method of  claim 1  wherein said hydrogel is a silicone hydrogel.  
     
     
         4 . The method of  claim 1  wherein said solution further comprises at least one buffer.  
     
     
         5 . The method of  claim 1  wherein said solution further comprises at least one chelating agent or sequestering agent.  
     
     
         6 . The method of  claim 1  wherein said solution further comprises at least one tonicity adjusting agent.  
     
     
         7 . The method of  claim 1  wherein said solution further comprises at least one surfactant.  
     
     
         8 . The method of  claim 1  wherein said solution comprises at least one pH adjusting agent.  
     
     
         9 . The method of  claim 1  wherein said solution comprises at least one viscosity builder.  
     
     
         10 . The method of  claim 1  wherein said solution comprises from about 0.0001 to about 10 weight percent cyclodextrin.  
     
     
         11 . The method of  claim 10  wherein said solution comprises from about 0.01 to about 2.0 weight percent cyclodextrin.  
     
     
         12 . A composition for rewetting, disinfecting and/or cleaning contact lenses comprising at least one biguanide antimicrobial and an amount of cyclodextrin that is insufficient of itself to effectively clean contact lenses if that amount of cyclodextrin were present in the solution in the absence of at least one other cleaning agent.  
     
     
         13 . The composition of  claim 12  wherein the biguanide antimicrobial is selected from the group consisting of poly(hexamethylene) biguanide and alexidine.  
     
     
         14 . The method of  claim 12  wherein said solution further comprises at least one buffer.  
     
     
         15 . The method of  claim 12  wherein said solution further comprises at least one chelating agent or sequestering agent.  
     
     
         16 . The method of  claim 12  wherein said solution further comprises at least one tonicity adjusting agent.  
     
     
         17 . The composition of  claim 12  wherein said aqueous solution further comprises buffers, chelating and/or sequestering agents, tonicity adjusting agents, surfactants, pH adjusting agents and viscosity builders.  
     
     
         18 . The composition of  claim 12  wherein said solution comprises from about 0.0001 to about 10 weight percent cyclodextrin.  
     
     
         19 . The composition of  claim 18  wherein said solution comprises from about 0.01 to about 2.0 weight percent cyclodextrin.  
     
     
         20 . The composition of  claim 12  wherein said amount of cyclodextrin is at least sufficient to inhibit sorption of a biguanide antimicrobial to said contact lenses.