6,332 publications from this institution
Scanning tunneling microscopy (STM) exploits the extreme distance sensitivity of electron tunneling to achieve atomic resolution imaging of surfaces. The ability of STM to probe directly materials on the atomic scale has been exploited to elucidate the structural effects of metal substitution in the copper oxide superconductor Bi2Sr2CuO6. A series of Bi2Sr2CuO6 single crystals containing lead substituted in the bismuth-oxide layer have been prepared, and the structures of these materials have been characterized by STM. The measurements show that lead-substitution induces complex changes in the structural order of the parent compound. Comparisons of these data with electron diffraction measurements highlight the importance of local crystallography, which STM provides, in studying the chemistry of inorganic materials.
This paper describes the synthesis of bifunctional polyacrylamides containing pendant vancomycin (Van) and fluorescein groups, and the use of these polymers to direct antibodies against fluorescein to self-assembled monolayers (SAMs) presenting d-alanine-d-alanine (dAdA) groups. These polymers bind biospecifically to these SAMs via interactions between the dAdA and Van groups and serve as a molecular bridge between the anti-fluorescein antibodies and the SAM. The binding events were characterized using surface plasmon resonance spectroscopy and fluorescence microscopy. The paper demonstrates that polyvalent, biospecific, noncovalent interactions between a polymer and a surface can be used to tailor the properties of the surface in molecular recognition. It also represents a first step toward the design of polymers that direct arbitrarily chosen antibodies to the surfaces of cells.
