Composite fluorescent vesicles based on ionic and cationic amphiphilic calix[4]arenes

Amphiphilic calixarenes bearing ionisable phosphonic acid groups or cationic trimethylamine groups attached to the upper rim of calix[4]arenes in the cone conformation, with dodecyl moieties attached to the lower rim, have a high uptake in PC-12 cells, with the calixarenes being localised cytoplasmically. The calixarenes form tightly packed layers, as established using scanning tunnelling microscopy (STM) on atomically flat surfaces, and can form vesicles or micelles. The vesicles have been wrapped in a peptide–glycol coat for enhanced stability.