Polymer and Protein Adsorption

Polymer and protein adsorption was studied quantitatively with an optical waveguide sensing technique, optical waveguide lightmode spectroscopy (OWLS). ... 

Table 1. Polymer and Protein Adsorption Data Measured with OWLS, Expressed as the Surface Density of PEG Chains and EG Monomers, npEc [nm ], reg [nm ], and the Mass of Adsorbed Serum, nisemm [Ng/ cm ], Standard Deviation ...

Samples, one half coated with SiOa and the other half with Ti02, were used for quantitative surface analysis after each of the siuface treatment steps (cleaning, self-assembly, and polymer and protein adsorption, section 2). These samples exhibit material contrast on a macroscopic scale and are discussed in section 3.1. Micropat-temed surfaces were subjected to identical siuface modification procedures and characterized qualitatively by imaging ToF-SIMS (section 3.2) and fluorescence microscopy (section 3.3) and were used in the cell experiments (section 3.4). In both types of samples, material contrast (on a macroscopic or microscopic scale, Figure la) is converted into contrast with respect to protein adhesion (Figure Ic) via a series of surface modification steps (self-assembly of DDP, adsorption of PLL-g-PEG section 2). 

Biomaterials with Low Thrombogenicity. Poly(ethylene oxide) exhibits extraordinary inertness toward most proteins and biological macromolecules. The polymer is therefore used in bulk and surface modification of biomaterials to develop antithrombogenic surfaces for blood contacting materials. Such modified surfaces result in reduced concentrations of ceU adhesion and protein adsorption when compared to the nonmodifted surfaces. 

RAIRS is routinely used for the analysis of chemically modified surfaces - surface systems in electrochemistry [4.277], polymer research [4.266, 4.278], catalysis [4.265, 4.271], selfassembling monolayers [4.267, 4.268], and protein adsorption [4.268, 4.279] have been investigated. 

So far ellipsometry has been used for adsorption from dilute solution, especially for surfactants, polymers and proteins. Examples will be given where appropriate. For further experimental details, we refer to the literature. ... 

Plasma protein interactions with polymer colloids Symmetrical Measurement of changes in particle (PS latex) size due to aggregation and adsorption of proteins effect of Pluronic surfactants on aggregation and protein adsorption [J.-T. Li and K. D. Caldwell, Colloids Surf. B Biointerfaces 7 9-22 (1996)]... 

Studies on polymer monolayers spread at the air-water interface are now in progress in our laboratory. Biocompatible and biodegradable polymers used as nanoparticles carrying biologically active substances are characterized using the surface balance, surface potential and protein adsorption/desorption measurements. The combined data of all these measurements provide information on drug and protein penetration/delivery with these polymers. 

Although ATR has been used to quantify the variation in composition at the surface in TPEs (Sung and Hu, 1980), a related utility is its ability to monitor in situ processes such as reaction injection molding (RIM) (Ishida and Scott, 1986) and protein adsorption onto a polyurethane substrate (Pitt and Cooper, 1986). In the latter, the effect of shear rate on the kinetics of protein adsorption and desorption from phosphate-buffered saline (PBS) was studied in a specially designed flow cell. A very thin film of the commercial MDI-ED-PTMO polyurethane Biomer was cast from solution onto a Ge ATR prism. The thickness of the film was less than the penetration depth so the protein concentration could be monitored after the infrared absorption of the polymer... 

There is no unified theory to explain the process of mucoadhesion. The total phenomenon of mucoadhesion is a combined result of all these theories. First, the polymer gets wet and swells (wetting theory) followed by the noncovalent (physical) bonds created within the mucus-polymer interface (electronic and adsorption theory). Then, the polymer and protein chains interpenetrate (diffusion theory) and entangle together to form further noncovalent (physical) and covalent... 

Table 5.2 Relationship between hydration state and protein adsorption on the polymer surfaces.

Zhan, X., et al., 2014. Preparation, surface wetting properties, and protein adsorption resistance of well-defined amphiphilic fluorinated diblock copolymers. Journal of Applied Polymer Science 131(23) n/a-n/a. 

Consider the relative change in interfacial area AA/A brought about by an external stress. Dilation leads to dilution of the monolayer which, in turn, results in a rise of the interfacial tension y. Conversely, reducing the interfacial area causes y to decrease. The response of the monolayer to the imposed deformation may be more or less elastic or viscous. Elastic behavior is expected for monolayers in which the amphiphilic molecules are interconnected forming a two-dimensional gel. Also, when the rate of deformation is too high to allow for relaxation back to equilibrium by, for example, adsorption or desorption of amphiphiles to or from the interface, or by reorientation and/or reconformation of the molecules in the monolayer (especially in the case of polymers and proteins), the monolayer responds partly elastically. 

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