Metallization of nanobiostructures: a theoretical study of copper nanowires growth in microtubules

A theoretical study of possible metallization sites within polypeptide structures is reported. The study has involved performing density functional B3LYP calculations in order to describe the affinities of various amino acids and larger peptide fragments towards copper ions. The results obtained for small amino acid systems have been used in the theoretical analysis of feasible metallization sites in large protein segments and in the whole proteins. The goal of this study was to explain the preferred inner-surface copper metallization of microtubules over outer-surface metallization. The inner-surface metallization is a new process that yields copper wires of 15 nm in diameter and may be used for fabrication of molecular interconnects at the nano-device level.