Surface mediated L-phenylalanyl-L-phenylalanine assembly into large dendritic structures.

We report a new class of dipeptide dendritic structures fabricated on the surface of mica via spin casting and the conditions required to achieve them. Both their structure and formation mechanism have been investigated in detail using Atomic Force Microscopy (AFM) at the nanometre scale. Formation of nanotubular structures and their further interaction is shown to be a key step in dendritic structure growth. A possible candidate for the primary building block in the nanotubular structure has been identified. The dendritic structures were found to be stable in ambient conditions for several months, however, they transform into needle-like crystals upon exposure to 100% (relative humidity) humid air.