| AVS 54th International Symposium | |
| Nanometer-scale Science and Technology | Monday Sessions |
| Session NS-MoM |
| Session: | Nanoscale Assembly and Manipulation I |
| Presenter: | M.L. Curri, CNR Italian National Research Council IPCF, Italy |
| Authors: | E. Fanizza, Università di Bari, Italy L. Malaquin, LPN CNRS, France T. Kraus, IBM Research GmbH, Zurich Research Laboratory, Switzerland H. Wolf, IBM Research GmbH, Zurich Research Laboratory, Switzerland M. Striccoli, CNR Italian National Research Council IPCF, Italy A. Agostiano, CNR Italian National Research Council IPCF, Italy M.L. Curri, CNR Italian National Research Council IPCF, Italy |
| Correspondent: | Click to Email |
Polystyrene (PS) beads have been functionalized with luminescent (CdSe)ZnS core shell type nanocrystal (NC), generating a versatile core-shell type of material, able to combine the size dependent optical property of (CdSe)ZnS NCs with the versatility and prompt processability for assembly of micrometer sized PS beads. The novel colloidal nanocomposite system has been fabricated by using a layer-by-layer (LbL) approach.1 Polystyrene beads have been firstly coated with polyelectrolyte (PE) layers and subsequently functionalized with fluorescent (CdSe)ZnS nanocrystals, synthesized following established procedure with minor adjustment. The obtained luminescent NC functionalized beads have been subsequently assembled onto patterned polydimethylsiloxane (PDMS) substrate by means of a capillary force induced process,2 thus providing an original example of physical directed assembly. Here the patterned stamp, fabricated with a top-down approach, act as template for the construction of well-defined discrete nanoscale structures at two- and three dimensions. The ordered fluorescent nanoparticle arrangement has been successful preformed by using two different patterns. A precise positioning of the PS functionalized beads has been achieved. Such original structures based on colloidal particles, which now carry the unique spectroscopic signatures of the luminescent NCs, are of considerable interest either in optoelectronic systems, and the ability to assembly and precisely positioning the functionalized nano-object into ordered assembly the venue to their prompt integration in bio-engineering due to their potential application in multiplexed bioassays, medical diagnostic, drug screening.3
1V. Salgueriño-Maceira, F. Caruso, L. Liz-Marzan, J. Phys. Chem. B, 2003, 107, 10990; M. Correa-Duarte, A. Kosiorek, W. Kanduloski, M. Giersig, L. Liz-Marzan, Chem. Mater., 2005, 17, 3268, F. Caruso, M. Spasova, A. Susha, M. Giersig, R.A. Caruso, Chem. Mater. 2001, 13, 109; H. Singh, O.E. Laibinis, T.A. Hatton, Langmuir 2005, 21, 11500; D. Wang, A. L. Rogach, F. Caruso, Nano lett. 2002, 2, 857
2T. Kraus, L. Malaquin, E Delamarche, H Schmid, N.D. Spencer, and H.Wolf. Adv. Mater., 2006, 17, 2438. L. Malaquin, T. Kraus, H. Schmid, E. Delamarche, H. Wolf, manuscript submitted.
3The partial support of the EC-funded project NaPa (Contract no. NMP4-CT-2003-500120) MIUR SINERGY programme (FIRB RBNE03S7XZ) is gratefully acknowledged.