Home About us Contact | |||
Stable Coatings (stable + coating)
Selected AbstractsCholesterol-rich membrane coatings for interaction studies in capillary electrophoresis: Application to red blood cell lipid extractsELECTROPHORESIS, Issue 20 2006Maria V. Lindén Abstract The purpose was to develop a stable biological membrane coating for CE useful for membrane interaction studies. The effect of cholesterol (chol) on the stability of dipalmitoylphosphatidylcholine (DPPC) and sphingomyelin (SM) coatings was studied. In addition, a fused-silica capillary for CE was coated with human red blood cell (RBC) ghost lipids. Liposomes prepared of DPPC/SM with and without chol or RBC ghost lipids were flushed through the capillary and the stability of the coating was measured electrophoretically. Similar mixtures of DPPC/SM with and without chol were further studied by differential scanning calorimetry. The presence of phosphatidylcholine as a basic component in the coating solution of DPPC/SM/chol was found to be essential to achieve a good and stable coating. The results also confirmed the stability of coatings obtained with solutions of DPPC with 0,30,mol% of chol and SM in different ratios, which more closely resemble natural membranes. Finally, the electrophoretic measurements revealed that a stable coating is formed when capillaries are coated with liposomes of RBC ghost lipids. [source] Interfacial Microstructure of Chromium Oxide Coatings,ADVANCED ENGINEERING MATERIALS, Issue 7 2007X. Pang This paper presents a study of chromium oxide coatings' interfacial microstructure and structural properties affecting coating performance. Amorphous chromium and chromium oxide layers about 100 nm thick were detected at the Cr/steel and the Cr/coating interfaces, providing a solution for depositing thicker mechanically stable coatings with improved hardness, smaller grain size, and smooth surface. [source] Capillary electrophoresis of intact basic proteins using noncovalently triple-layer coated capillariesJOURNAL OF SEPARATION SCIENCE, JSS, Issue 14 2009Rob Haselberg Abstract The usefulness of a noncovalent, positively charged capillary coating for the efficient analysis of intact basic proteins with CE was studied. Capillaries were coated by subsequent flushing with solutions of 10% w/v Polybrene (PB), 3% w/v dextran sulfate (DS), and again 10% w/v PB. Coating characterization studies showed that stable coatings could be produced which exhibited a pH-independent and highly reproducible EOF. The PB,DS,PB coating was evaluated with Tris phosphate BGEs of various pH using the four basic model proteins: ,-chymotrypsinogen A, ribonuclease A, cytochrome c, and lysozyme. Typical migration time RSDs for the proteins were less than 0.85%, and apparent plate numbers were above 125 000 using a capillary length of 40 cm. The high separation efficiency allowed detection of several minor impurities in the model proteins. Using a BGE of medium pH, the CE system with triple-layer coating appeared to be useful for the repeatable profiling of recombinant humanized mouse monoclonal immunoglobulin G1 showing a characteristic pattern of glycoforms. The CE system was also applied to the characterization of two llama antibodies, which were produced in Saccharomyces cerevisiae, revealing the presence of a side product in one of the antibodies. The high migration time stability allowed the reliable determination of antibody,antigen binding by monitoring migration time shifts. Finally, the feasibility of using the PB,DS,PB coated capillaries for CE with mass spectrometric detection was shown by the characterization of the impure llama antibody sample. [source] Nanoparticles by chemical synthesis, processing to materials and innovative applications,APPLIED ORGANOMETALLIC CHEMISTRY, Issue 5 2001Helmut Schmidt Abstract Nanoparticles have been fabricated by using chemical synthesis routes under specific conditions. During a precipitation process from liquid phases, surface controlling agents (SCAs) have been added during or shortly after the formation of precipitates. These interfere with the nucleating and growing particle to avoid agglomeration and to control size. Nanoparticles from many systems have been fabricated. If the SCAs are bifunctional, the surfaces chemistry could be tailored and the zeta potential of these particles was tailored also. SiO2 particles have been used for gene targeting using this approach. In other investigations, FeOx nanoparticles have been surface modified by amino groupings together with a sonochemical route to obtain very stable coatings. These particles have been used for in vitro tumor cell penetration and hyperthermal treatment. Boehmite nanoparticles were used to serve as condensation catalysts to prepare very hard transparent coatings for polycarbonate and an overcoat with polymerizable nanoparticles was used to produce anti-reflective and ultrahard coatings. In systems with incorporated fluoro silanes, leading to low surface free energy coatings, nanoparticles were used to tailor the fluorine depth profile in self-aligning transparent easy-to-clean coatings by influencing the critical micelle concentration. The examples show the usefulness of the chemical nanoparticle approach for nanocomposite fabrication and the high potential of these materials for medical and industrial application. Copyright © 2001 John Wiley & Sons, Ltd. [source] |