AmericanChemicalSociety.com

This grant provided travel support for 2 invited international  speakers to facilitate a symposium on “Patchy Surfaces and Interfaces” within the Colloid and Surface Chemistry Division of the American Chemical Society (ACS), at the 238th National ACS Meeting in August 2009 in Washington DC. Following the meeting,  a website was created to disseminate technical information to those unable to attend the symposium.  Overall the symposium boasted  eleven invited speakers, supported by PRF and other means, including matching moneys from the COLL division.  The symposium took place for 2 full days, on August 19 and 20 in the Ronald Regan building.  The talks were extremely well attended, with roughly 200 people in the audience.  Subject matter ranged from methods for preparing and characterizing patchy surfaces and particles (with patchy lengthscales from 10 nm up to about half a micron), to investigations of the unique properties of deriving from interfacial patchiness.  Discussions included application to complex fluids, relevant to oil recovery.

Here is a list of all the invited speakers.  Adamczyk and Spatz were supported by PRF.  

-  N.J. Halas,  “Symmetry-Breaking Plasmonic Nanostructures:  New Properties Driving New Synthetic Opportunities” This talk explored optical properties of assemblies of structured colloids.

-  I. Kretzschmar “Patchy Particles”  This talk detailed methods to  create patchy particles and examined their assembly behavior.

J. C. Garno “High-Throughput Nanoscale Patterning using Particle Lithography:  Characterizations Using Atomic Force Microscopy”  This talk explored means to nano-pattern large areas of surface with a variety of materials through very economic means.

D. Velegol and H.A. Jerri, “Fabrication of Anisotropic Focus-Released Microcapsules”  This talk explored the creation of patchy hydrogel particles and their use in targeted release applications.

T.A. Camesano “Role of LPS Heterogeneity on Adhesio of Gram-Negative Bacteria”   This talk explored how heterogeneities on the surface of bacteria controlled bacterial adhesion and correlated with virulence.

D.J. Pine “Structured Colloids: Patches, Packmen, and Helices”  This talk demonstrated the creation of a variety of patterned particles that either assembled in a self-replicating fashion or demonstrated lock and key selective binding, the latter without the use of biomolecular fragments.

E. Luijten “Assembly Behavior of Janus Particles and the Role of Hydrodynamic Interactions”  This talk explored the influence of hydrodynamic coupling on the assembly of janus-type patterned particles.

J.P. Spatz “Nanopattern Surfaces for Molecular Engineering of Cellular Environments”  This talk explored the interactions of cells with nanopatterned surfaces.  Among the interesting findings was a sharp 60 nm threshold in feature spacing, below which cells adhered, and above which materials were significantly less adhesive towards the cells.

J.M.Davis “Particle Interactions with Patchy Surfaces in Flow”  This talk showcased modeling studies of particle adhesion on patchy surfaces in the presence of flow, for assembly and bioadhesive applications.

Z. Adamczyk “Deposition of Particles at Heterogeneous and Patterned Surfaces”  This presentation explored experimental studies of particle deposition on patchy surfaces focusing on dynamic and structural aspects of the interfaces.

M. Santore “Using Patchy Surfaces for Selective Particle and Cell Adhesion and Dynamic Motion Control”  This talk demonstrated biomimetic features of particle adhesion on nano-patchy surfaces:  sharply selective particle binding without use of biomolecular fragments, and control of adhesion dynamics and signature, including particle rolling for separations and sensing.