U.S.-Japan Young Scientists Symposium on BioNanotechnology

Atom Manipulation at Room Temperature Using Atomic Force Microscopy Masayuki Abe, Osaka University [email protected] Creation of artificial atomic structure formed on a surface by scanning tunneling microscopy has given us possibilities in future nanoengineering. These experiments of lateral atom manipulation, however, have been demonstrated only at low temperature. So far, at room temperature, it was thought that there are some difficulties to manipulate atoms because atoms on a surface move unexpectedly due to thermal energy. We demonstrate, for the first time, well-controlled lateral manipulations of single atoms using atomic force microscopy (AFM) at room temperature. Substitutional Sn and Ge adatoms in the plane of the Ge(111)-c(2x8) surface are interchanged laterally using AFM tip which is closed to the surface. This induced interchange between Sn and Ge adatoms can be controlled by appropriate tip scan direction and measurements of short-range interaction force between atoms of the AFM tip apex and the surface. We created ‘atom inlay’, that is, artificial atomic pattern formed from embedded Sn atoms in the plane of the surface at room temperature. We believe that this result drives us closer to the ultimate limit of two-dimensional nanoengineering. Biomedical Micro/Nanodevices for Therapeutic Targeting and Delivery Tejal Desai, Boston University [email protected] Micro and nanofabrication techniques, which permit the creation of multifunctional platforms that possess a combination of structural, mechanical, and electronic features, may surmount several challenges associated with the conventional delivery of therapy. In this talk, in vivo delivery concepts are presented which capitalize on the strengths of nanofabrication coupled with tailoring of surface chemistry. Current work on targeted nanostructures for neural applications, nanoporous implantable biocapsules for the immunoisolation of pancreatic and neurosecretory cells, and asymmetrical, reservoir-containing microfabricated particles for the oral delivery of peptides and drugs will be presented. The key driving force is the complementary length scale between biological structures that range from the 10s of nanometers (proteins, DNA, viruses) to the micron scale (cells and cellular assemblies) and the new capabilities of micro/nanosystems to manipulate and control such feature sizes within our environment. U.S.-Japan Young Scientists Symposium on BioNanotechnology 2