Protection/Deprotection of surface activity and its applications in the controlled release of liposomal contents.
The micelles of two tripropargylammonium-functionalized cationic surfactants were cross-linked by a disulfide-containing diazido cross-linker in the presence of Cu(I) catalysts. With multiple residual alkyne groups on the surface, the resulting surface cross-linked micelles (SCMs) were postfunctionalized by reaction with 2-azidoethanol and an azido-terminated poly(ethylene glycol), respectively, via the alkyne-azide click reaction. The water-soluble nanoparticles obtained had low surface activity due to the buried hydrophobic tails. Cleavage of the disulfide cross-links by dithiothreitol (DTT) exposed the hydrophobic tails and resumed surface activity of the "caged" surfactants within 2 min after DTT addition. The controlled breakage of the SCMs was used to lower the surface tension of aqueous solutions and trigger the release of liposomal contents on demand.
Department of Chemistry, Iowa State University, Ames, Iowa 50011-3111, United States.
Xueshu
X
Li
Yan
Y
Zhao
D004229:Dithiothreitol / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry
D008081:Liposomes; D000644:Quaternary Ammonium Compounds; D013501:Surface-Active Agents; C048939:tripropylammonium; D011092:Polyethylene Glycols; D004229:Dithiothreitol