Self-assembly of protoporphyrin IX-TEG derivatives into tunable nanoscaled spherical structures

The results of a solvo-controlled self-assembly process involving a novel non-ionic protoporphyrin IX functionalized with triethylene glycol (Proto-NTEG) chains is discussed. In relatively non-polar aprotic solvents (cyclohexane/CHCl(3)), the protoporphyrin forms stable, uniformly-sized multilamellar micro-vesicles of approximately 65 nm diameter, while in more polar protic solvent mixes (CHCl(3)/MeOH), the same protoporphyrin forms micellar aggregates with dimensions of approximately 6 nm. The solvo-control operates based on the differing properties of glycol units in cyclohexane and methanol leading to inverse self-assembled structures.