BIOMOLECULAR APPROACH TO NANOTUBE FABRICATION

We report on parallel fabrication of identical nanotubes by electroles s metal him deposition on to tubular biomolecular templates. As templa tes we used microtubules, in vitro assembled protein filaments with a 25 nm outer diameter and a length of several micrometer. By depositing about 10 nm nickel or cobalt, magnetic nanowires with an outer diamet er of 50 nm have been produced. The deposition is initiated by direct adsorption of metallic Pd or Pt catalysts onto the microtubule surface s. Since the distribution of catalyst particles is crucial for the hom ogeneity of the subsequently deposited metal film, the surface activat ion of microtubules by molecular catalysts is studied in more detail. In distinction to other protein surfaces such as regular bacterial sur face layer proteins the microtubule surface provides a random distribu tion of catalyst particles.