Self-Assembly of Amphiphilic Calix[4]arenes in Aqueous Solution

The self‐assembly of amphiphilic calix[4]arenes with either a carboxylic acid or a trimethyl ammonium head group and different alkyl chains in aqueous solution was investigated. The carboxylated calixarene forms vesicles in dilute solution and stable monolayers on water. In contrast, the ammonium head group provides high water solubility with no observed aggregation. At high concentrations, all calixarene amphiphiles form lyotropic liquid crystals. Self‐assembly of amphiphilic calix[4]arenes (see Figure) with carboxylic acid/trimethyl ammonium head groups and different alkyl chains in aqueous solution has been investigated. Carboxylated calixarenes form vesicles in dilute solution and stable monolayers on water. Ammonium head groups provide high water solubility without detectable aggregation. The head group is therefore shown to be the key parameter in controlling self‐assembly in aqueous solution.