Microcontact printing of metalloproteins

The morphological investigation by scanning probes techniques, and especially Atomic Force Microscopy (AFM) allow to measure the surface roughness of immobilized proteins with unequalled vertical spatial resolution. This is particularly important, since the biological role of proteins is closely related to their physiological folding architectures. In particular, metalloproteins, such as blue copper proteins, revealed to be good candidates for biomolecular electronics by virtue of their natural electron transfer activity, which is exploitable in molecular switches whose conduction state can be controlled by gating their redox state. The interest in these molecules is indeed motivated by the possibility of eliciting current flow through the redox level of single molecules. Printing metalloproteins can be an advantageous approach for the easy realization of bioelectronic circuits. We implemented and developed the selective deposition of the metalloprotein Azurin (Az) from Pseudomonas aeruginosa by microcontact printing, and investigated by AFM the surface morphology of the printed Az layers.