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The sum frequency vibrational spectrum in the C-H stretching region of a comb copolymer, cetyl dimethicone copolyol (CDC), consisting of a poly(dimethylsiloxane) backbone and grafted poly(ethyleneoxide) are recorded after deposition on a gold-coated substrate. The SF resonance attributes to the methyl groups of the polymer backbone and the cetyl side chains of polymer are observed.

A theoretical model is developed to describe the generation of Sum Frequency (SF) light from a monolayer film adsorbed to the surface of a diaelectric and metal composite substrate. This type of substrate provides enhanced SF signals from the monolayer without modifying the intrinsic (hydrophilic) properties of the dielectric surface.

Research was conducted to examine are determine the average orientation of the methylene tail of cetyltrimethylammonium bromide (CTAB) using polarized infrared attenuated reflection. Calculations were made of the methylene absorbance bands of CTAB adsorbing on silica in the S and P polarized states. Results indicate that surfactant desorption occurs in localized areas and that the residual surfactant is present in isolated clusters of highly ordered molecules that take a considerable time to relax their orientation.

Sum frequency generation (SFG) vibrational spectra of cadmium arachidate multilayer films adsorbed on a substrate with high nonresonant susceptibility on a low nonresonant susceptibility substrate are investigated. The films were formed by Langmuir-Blodgett deposition and their spectra recorded using SFG spectrometers employing both 532-nm nanosecond and 800-nm femtosecond lasers, with counter-propagating beam geometries respectively.

A novel substrate consisting of calcium phosphate sputter coated onto a gold film is chemically and morphologically characterized. Results reveal that the surface is primarily calcium phosphate present as a mixture of amorphous, non-hydroxylated phases rather than solely stoichiometric hydroxypatite.

The nonlinear optical technique of sum frequency generation (SFG) vibrational spectroscopy is used for investigating the order of the fatty acid molecules in the composite nanoparticle fatty acid multilayer structure. The difference in ordering between the surface layer and the bulk of the film after the incorporation of CdS nanoparticles show the importance of the van der Waals interaction in stabilizing these films and the flexibility of the fatty acid molecules.

The phase behavior of the r(super -1) methyl resonance is successfully modeled by the extension of a previously developed interference theory to include multiple reflections and a resonant contribution from the polymer/gold interface.

Langmuir-Blodgett multilayer films of cadmium salts of fatty acids deposited onto hydrophobic gold surfaces have been found to be sum frequency active in the C-H stretching region is discussed. These findings imply that interpretation of SF spectra of LB multilayer films deposited on metal substrates must be performed with care and that deconvolution of spectra in terms of contributing layers is imperative.

A composite dielectric/metal substrate, consisting of a thin mica sheet backed with a gold film, are employed to enhance the intensity of sum frequency vibrational spectroscopy (SFS) signals arising from model monolayers of octadecylsiloxane (ODS) adsorbed at the mica/air interface. Further, the interference phase/thickness effect is investigated for several composite samples.

Surfactant-coated gold nanoparticles were studied for frequency generation.

The formation of biomimetic lipid membranes has the potential to provide insights into cellular lipid membrane dynamics. The construction of such membranes necessitates not only the utilization of appropriate lipids, but also physiologically relevant substrate/support materials. The substrate materials employed have been shown to have demonstrable effects on the behavior of the overlying lipid membrane, and thus must be studied before use as a model cushion support. To our knowledge, we report the formation and investigation of a novel actin protein-supported lipid membrane. Specifically, inner leaflet lateral mobility of globular actin-supported DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) bilayers, deposited via the Langmuir-Blodgett/Langmuir Schaefer methodology, was investigated by z-scan fluorescence correlation spectroscopy across a temperature range of 20-44°C. The actin substrate was found to decrease the diffusion coefficient when compared to an identical membrane supported on glass. The depression of the diffusion coefficient occurred across all measured temperatures. These results indicated that the actin substrate exerted a direct effect on the fluidity of the lipid membrane and highlighted the fact that the choice of substrate/support is critical in studies of model lipid membranes., (Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.)