An experimental setup has been constructed for simultaneous measurements of the frequency, absolute Q factor, and amplitude oscillation a quartz crystal microbalance (QCM). The technical solution allows operation in vacuum, air, or liquid. is driven at its resonant frequency by an oscillator that can be intermittently disconnected causing to decay exponentially. From recorded curve factor (calculated from time constant), freely oscillating crystal, are obtained. All fully automated. One...

We have measured the energy dissipation of quartz crystal microbalance(QCM), operating in liquid phase, when mono- or multi-layers bio-molecules and biofilms form on QCM electrode (with a time resolution ca. 1 s). Examples are taken from protein adsorption, lipid vesicle adsorption cell adhesion studies. Our results show that even very thin (a few nm) dissipate significant amount owing to oscillation. Various mechanisms for this discussed. Three main contributions increase considered. (i) A...

(111) textured Au films were oxidized under UHV conditions by exposing them to UV radiation and ozone. The characterized x-ray photoelectron spectroscopy. gold surface becomes heterogeneous upon oxidation: approximately 0.8 monolayer (ML) of the adsorbed oxygen is present as chemisorbed species. rest forms, on average, a few ML thick oxide with stoichiometry close Au2O3. Both disappear slowly when heated 150 °C. During isothermal decomposition at 200 °C, transformed prior desorption. can be...

With today's developments of biosensors and medical implants comes the need for efficient reduction nonspecific binding. We report on a comparison ability traditionally used blocking agents poly(ethylene glycol) (PEG) derivatives to prevent protein adsorption both gold polystyrene surfaces. The kinetics molecules proteins was monitored gravimetrically using quartz crystal microbalance with dissipation (QCM-D). resistance evaluated surfaces coated bovine serum albumin (BSA) or casein, three...

We developed nanoparticles with tailored magnetic properties for direct and sensitive detection of biomolecules in biological samples a single step. Thermally blocked obtained by thermal hydrolysis, functionalized specific ligands, are mixed sample solutions, the variation relaxation due to surface binding is used detect presence biomolecules. The significantly increases hydrodynamic volume nanoparticles, thus changing their Brownian frequency which measured specifically AC susceptometer....

The properties of thin films (0.03−2 μm) high-density polyethylene spin-coated at elevated temperatures (100−180 °C) onto silicon wafers and evaporated gold were investigated. coatings characterized with respect to thickness (ellipsometry, QCM), chemical composition (ESCA, TOF-SIMS), morphology (optical microscopy, AFM). Initial deposition temperature was found be an important process parameter that affected the crystal morphology, uniformity, films. nucleation growth depend on both...

Using magnetic particles with sizes in the nanometer range biomedical separation has gained much interest recently due to their higher surface area particle volume and lower sedimentation rates. In this paper, we report our both theoretical experimental investigation of motion a field gradient from 425 nm down 50 nm. measurements, monitor absorbance change sample as concentration varies over time. We also implement Brownian dynamics algorithm investigate influence interactions during compare...

The hydrogen concentration in Mg equilibrium with H2 gas, and the associated kinetics, were measured at 103-105 times lower pressure than previously reported, by using UHV-prepared samples a thin Pd coating. Equilibrium can be established above (pressure-dependent) critical temperature below which interface hydride formation Pd/Mg prevents equilibration. new data agree well extra-polations of high-pressure data. Absorption decomposition isotherms beta -phase (plateau region) show large...

The kinetic equations are formulated and solved to describe a first-order phase transition initiated by diffusion of particles from the surface into bulk. scenario transformation is assumed involve following three stages. At first, diffuse in bulk almost freely because grain concentration low. Then, with increasing concentration, trapped predominantly near interface space distribution shifts interface. Finally, dense formed blocks prevents further uptake. General results used interpret...

ABSTRACT Background : It has been suggested that calcium phosphate (CaP) coatings initiate faster bone growth around implants. A major concern about the viable use of these their biologic performance related to coating characteristics. Purpose The purpose this study was investigate early response micron‐ and submicron‐thick hydroxya‐patite (HA) in cortical trabecular bone. Materials Methods CaP were manufactured by magnetron sputtering. Heat treatment subsequently used increase crystallinity...

The hydriding of thick Mg films with a 50–100 Å Pd film on top, as catalyst for H2 dissociation, was investigated by quartz-crystal microbalance uptake measurements in combined UHV and high-pressure equipment. Unusual kinetics are observed: (i) the hydrogen saturates far from MgH2 at room temperature (ii) saturation decreases increasing pressure. results explained terms interface hydride formation Pd/Mg interface, which blocks diffusion. A theoretical basis this model is given combining...

Microbial plaque accumulation on titanium dental implant surfaces can result in an inflammatory condition of the surrounding tissues. Cleaning such a contaminated surface, viva, by means solution amino‐alcohol, following surgical exposure, has been proposed. However, tissue healing treatment resulted formation fibrous capsule at tissue‐implant interface, i.e. improper re‐integration.The present experiment was designed to investigate possible influence amino‐alcohol machined surface...

Abstract Ultraviolet (UV) treatment is an effective method for modification of the surface properties polymeric materials. In this study, effects ozone‐generating UV light thin high‐density polyethylene (HDPE) films were monitored with quartz crystal microbalance (QCM) technique both in presence ozone and without it. The further characterized by X‐ray photoelectron spectroscopy, optical microscopy, atomic force microscopy. We found that not only modified HDPE but also etched away polymer...