Tuneable Fmoc-Phe-(4-X)-Phe-NH2 nanostructures by variable electronic substitution.

Supramolecular structures were produced by in situ enzymatic condensation of Fmoc-Phe-(4-X), where X denotes electron withdrawing or donating groups, with Phe-NH2. The relative contribution of π-stacking and H-bonding interactions can be regulated by the nature of X, resulting in tuneable nanoscale morphologies.