Surfactant composition having stable hydrophilic character

Abstract

Hydrophilic surfactant compositions are disclosed that include a surfactant component and a stabilizer component. The surfactant can be coated on a surface by depositing a surfactant solution on at least a portion of the surface, then drying the surfactant solution to form the dry coating. The surfactant compositions, when applied to a substrate, can provide a hydrophilic surface that retains its hydrophilic character over time, at elevated temperatures, or both.

1 . A microfluidic device for exposure to body fluids, comprising
 a substrate;   a coating comprising a surfactant component from about 25% to 95% by weight on a solvent-free basis and a stabilizer component from about 5% to 75% by weight on a solvent-free basis;   
       wherein the contact angle of the coating does not exceed 25 degrees after aging for thirteen weeks at 25° C. 
     
     
         2 . The microfluidic device of  claim 1 , wherein the substrate is non-porous. 
     
     
         3 . The microfluidic device of  claim 1 , wherein the substrate is a film. 
     
     
         4 . The microfluidic device of  claim 1  wherein the surfactant component is a liquid at temperatures below 25° C. 
     
     
         5 . The microfluidic device of  claim 1  wherein the surfactant component is a nonionic surfactant. 
     
     
         6 . The microfluidic device of  claim 1  wherein the surfactant component is selected from the group consisting of alkoxylated alkyl diol; alkoxylated alkyacetylenic diol; alkoxylated glycerin monoester of an alkyl alcohol; alkoxylated glycerin monoester of an aralkyl alcohol; alkoxylated alkyl alcohol; polyalkoxylated aralkyl alcohol; silicone copolyol; polyethoxylated phenol; a fatty acid ester of a polyalkoxylated diol; a fatty acid ester of a polyalkoxylated triol, and polyalkoxylated perfluoroalkyl-containing surfactant. 
     
     
         7 . The microfluidic device of  claim 1  wherein the stabilizer component has a melting point greater than 25° C. 
     
     
         8 . The microfluidic device of  claim 1  wherein the stabilizer component has a melting point of at least 45° C. 
     
     
         9 . The microfluidic device of  claim 1  wherein the stabilizer component is selected from the group consisting of anionic perfluoroalkyl-containing surfactant; alkyl, aralkyl or alkaryl sulfonate; alkyl, aralkyl or alkaryl sulfate; alkyl, aralkyl or alkaryl phosphonate; alkyl, aralkyl or alkaryl phosphate; aralkyl or alkaryl phosphonate; alkyl, aralkyl or alkaryl betaine; aralkyl or alkaryl phosphonate sultaine; and fatty imidazolines and derivatives thereof. 
     
     
         10 . The microfluidic device of  claim 1  wherein the hydrophilic characteristics indicated by the spreading drop diameter retaining at least 90% of the original drop diameter after 3 weeks of aging at 23° C. and 50% relative humidity. 
     
     
         11 . The microfluidic device of  claim 1  wherein the hydrophilic characteristics indicated by the spreading drop diameter retaining at least 95% of the original drop diameter after 3 weeks of aging at 23° C. and 50% relative humidity. 
     
     
         12 . A method of making a hydrophilic surface on a substrate, comprising:
 Combining a surfactant component from about 0.2% to 0.6%, a stabilizer component from about 0.05% to 0.5%; and a solvent to form a surfactant composition,   Applying the surfactant composition to a substrate, and   Drying the surfactant composition on the substrate,   
       wherein the surfactant composition free of the solvent when dried and coated on a substrate comprises the surfactant and stabilizer in a ratio of 0.2:1 to 12:1 wt/wt and wherein the hydrophilic characteristics indicated by a Spreading Drop Test retain at least 85% of the original spreading drop diameter after 3 weeks of aging at 23° C. and 50% relative humidity. 
     
     
         13 . The method of  claim 12 , wherein the substrate is non-porous. 
     
     
         14 . The method of  claim 12 , wherein the substrate is a film. 
     
     
         15 . The method of  claim 12  wherein the solvent comprises a mixture of water and alcohol. 
     
     
         16 . The method of  claim 12  wherein the alcohol is selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, and butanol. 
     
     
         17 . The method of  claim 12  wherein the surfactant component is a nonionic surfactant. 
     
     
         18 . The method of  claim 12  wherein the surfactant component is selected from the group consisting of alkoxylated alkyl diol; alkoxylated alkyacetylenic diol; alkoxylated glycerin monoester of an alkyl alcohol; alkoxylated glycerin monoester of an aralkyl alcohol; alkoxylated alkyl alcohol; polyalkoxylated aralkyl alcohol; silicone copolyol; polyethoxylated phenol; a fatty acid ester of a polyalkoxylated diol; a fatty acid ester of a polyalkoxylated triol, and polyalkoxylated perfluoroalkyl-containing surfactant. 
     
     
         19 . The method of  claim 12  wherein the stabilizer component has a melting point greater than 25° C. 
     
     
         20 . The method of  claim 12  wherein the stabilizer component is selected from the group consisting of anionic perfluoroalkyl-containing surfactant; alkyl, aralkyl or alkaryl sulfonate; alkyl, aralkyl or alkaryl sulfate; alkyl, aralkyl or alkaryl phosphonate; alkyl, aralkyl or alkaryl phosphate; aralkyl or alkaryl phosphonate; alkyl, aralkyl or alkaryl betaine; aralkyl or alkaryl phosphonate sultaine; and fatty imidazolines and derivatives thereof.