Decoration of Au and Ag Nanoparticles on Self-Assembling Pseudopeptide-Based Nanofiber by Using a Short Peptide as Capping Agent for Metal Nanoparticles Partha Pratim Bose, † Michael G. B. Drew, ‡ and Arindam Banerjee* ,†,§ Department of Biological Chemistry, Indian Association for the CultiVation of Science, JadaVpur, Kolkata 700032, India, Chemistry DiVision, Indian Institute of Chemical Biology, JadaVpur, Kolkata 700032, India, and School of Chemistry, The UniVersity of Reading, Whiteknights, Reading, United Kingdom RG6 6AD bcab@mahendra.iacs.res.in; arindam@iicb.res.in Received April 11, 2007 ABSTRACT The surface of a nanofiber that is formed from a self-assembling pseudopeptide has been decorated by gold and silver nanoparticles that are stabilized by a dipeptide. Transmission electron microscopic images make the decoration visible. In this paper, a new strategy of mineralizing a pseudopeptide based nanofiber by gold and silver nanoparticles with use of a two-component nanografting method is described. The shape and size of nanocrystals govern their catalytic, optical, and electronic properties. 1 To apply nanocrystals as building blocks for practical electronic, magnetic, and optical devices, the nanocrystals must be assembled in an ordered pattern. There are some recent examples of patterned deposition of various nanocrystals on flat surfaces. 2 Recent studies include the patterning of the nanocrystals on cylindri- cal nanotube surfaces. 3 Controlling diameter and packing densities of nanocrystals on the surfaces on which they are to be patterned is of utmost importance to produce nanode- vices with tunable electronic properties from a single type of nanocrystal. Biological systems control the mineralization and nanocrystal synthesis of various metals in exact shapes and sizes with high accuracy. 4 There are many examples of using biological molecules as templates on which the † Indian Association for the Cultivation of Science. ‡ The University of Reading. § Indian Institute of Chemical Biology. (1) (a) Puntes, V. F.; Krishnan, K. M.; Alivisatos, A. P. Science 2001, 291, 2115-2117. (b) Puntes, V. F.; Zanchet, D.; Erdonmez, C. K.; Alivisatos, A. P. J. Am. Chem. Soc. 2002, 124, 12874-12880. (c) Orendroff, C. J.; Sau, T. K.; Murphy, C. J. Small 2006, 2, 636-639. (d) Orendroff, C. J.; Gearheart, L. A.; Jana, N. R.; Murphy, C. J. PhysChemChemPhys 2006, 8, 165-170. (e) Jin, R. C.; Cao, Y. W.; Mirkin, C. A.; Kelly, K. L.; Schatz, G. C.; Zheng, J. G. Science 2001, 294, 1901-1903. (f) Gou, L. F.; Murphy, C. J. Nano Lett. 2003, 3, 231-234. (2) (a) Xu, J.; Drelich, J.; Nadgorny, E. M. Langmuir 2004, 20, 1021- 1025. (b) Wei, Z.; Zamborini, F. P. Langmuir 2004, 20, 11301-11304. (c) Gittins, D. I.; Susha, A. S.; Schoeler, B.; Caruso, F. AdV. Mater. 2002, 14, 508-512. (d) Sun, S.; Mendes, P.; Critchley, K.; Diegoli, S.; Hanwell, M.; Evans, S. D.; Leggett, G. J.; Preece, J. A.; Richardson, T. H. Nano. Lett. 2006, 6, 345-350. (e) Heriot, S. Y.; Pedrosa, J.-M.; Camacho, L.; Richardson, T. H. Mater. Sci. Eng. 2006, C 26, 154-162. (3) (a) Dujardin, E.; Peet, C.; Stubbs, G.; Culver, J. N.; Mann, S. Nano Lett. 2003, 3, 413-417. (b) Behrens, S.; Rahn, K.; Habicht, W.; Bohm, K.-J.; Rosner, H.; Dinjus, E.; Unger, E. AdV. Mater. 2002, 14, 1621-1625. ORGANIC LETTERS 2007 Vol. 9, No. 13 2489-2492 10.1021/ol0708471 CCC: $37.00 © 2007 American Chemical Society Published on Web 06/02/2007