Eur. Phys. J. D 38, 117-120 (2006)
https://doi.org/10.1140/epjd/e2006-00043-1

Amino acid adsorption on single-walled carbon nanotubes

¹ Department of Applied Physics, Osaka University, Suita, Osaka, 565-0871, Japan
² Department of Physics, Osaka University, Toyonaka, Osaka, 560-0043, Japan
³ Physics Department, De La Salle University, Manila, 1004, Philippines

Corresponding author: ^a kasai@dyn.ap.eng.osaka-u.ac.jp

Received: 12 September 2005
Revised: 1 December 2005
Published online: 21 February 2006

Abstract

We investigate and discuss the adsorption of a few amino acids on (3,3) carbon nanotubes and on graphite sheets through calculations within density functional theory. Results show weak binding of the biomolecules on both substrates, but through generally favourable adsorption pathways. Zwitterion adsorption through the charged amine and carboxylate groups are bound stronger to the nanotube surface in comparison to their nonionic counterparts, as well as on histidine, phenylalanine, and cysteine side chain groups fixed in specific orientations. Binding strengths on graphite suggest dissimilar trends for amino acid interactions with increasing nanotube diameter.