Ames Laboratory; Physics and Astronomy; Chemical and Biological Engineering
Chemical and Biological Engineering, Physics and Astronomy, Ames Laboratory
In-situ X-ray reflectivity (XRR) and grazing incidence X-ray small-angle scattering (GISAXS) reveal that unfunctionalized (bare) gold nanoparticles (AuNP) spontaneously adsorb to a cationic lipid template formed by a Langmuir monolayer of DPTAP (1,2-dihexadecanoyl-3-trimethylammonium-propane) at vapor/aqueous interfaces. Analysis of the XRR yields the electron density profile across the charged-interfaces along the surface normal showing the AuNPs assemble with vertical thickness comparable to the particle size. The GISAXS analysis indicates that the adsorbed mono-particle layer exhibits short-range in-plane correlations. By contrast, single-stranded DNA-functionalized AuNPs, while attracted to the positively charged surface (more efficiently with the addition of salt to the solution), display less in-plane regular packing compared to bare AuNPs.
DOE Contract Number(s)
Department of Energy Subject Categories
77 NANOSCIENCE AND NANOTECHNOLOGY; 36 MATERIALS SCIENCE
Iowa State University Digital Repository, Ames IA (United States)