The Experts below are selected from a list of 38805 Experts worldwide ranked by ideXlab platform
Yasuhisa Sakurai - One of the best experts on this subject based on the ideXlab platform.
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mechanism of cell detachment from temperature modulated hydrophilic Hydrophobic Polymer surfaces
Biomaterials, 1995Co-Authors: Teruo Okano, Noriko Yamada, Minako Okuhara, Hideaki Sakai, Yasuhisa SakuraiAbstract:Abstract Poly( N -isopropylacrylamide) (PIPAAm), exhibiting a lower critical solution temperature (LCST) at 25 °C in physiological phosphate buffered saline solution (pH 7.4) and at 32 ° C in pure water, was grafted onto the surfaces of commercial polystyrene cell culture dishes. This PIPAAm-grafted surface exhibited Hydrophobic surface properties at temperatures over the LCST and hydrophilic surface properties below the LCST. Endothelial cells and hepatocytes attached and proliferated on PIPAAmgrafted surfaces at 37 ° C, above the LCST. The cultured cells were readily detached from these surfaces by lowering the incubation temperature without the usual damage associated with trypsinization. In this case, the optimum temperature for cell detachment was 10 ° C for hepatocytes and 20 ° C for endothelial cells. Cell detachment was partially inhibited by sodium azide treatment, suggesting that cell metabolism directly affects cell detachment. Morphological changes of the adherent cells during cell detachment experiments indicated further involvement of active cellular metabolic processes. Cells detached from Hydrophobic-hydrophilic PIPAAm surfaces not only via reduced cell surface interactions caused by the spontaneous hydration of grafted PIPAAm chains, but also by active cell morphological changes which were a function of cell metabolism.
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mechanism of cell detachment from temperature modulated hydrophilic Hydrophobic Polymer surfaces
Biomaterials, 1995Co-Authors: Teruo Okano, Noriko Yamada, Minako Okuhara, Hideaki Sakai, Yasuhisa SakuraiAbstract:Poly(N-isopropylacrylamide) (PIPAAm), exhibiting a lower critical solution temperature (LCST) at 25 degrees C in physiological phosphate buffered saline solution (pH 7.4) and at 32 degrees C in pure water, was grafted onto the surfaces of commercial polystyrene cell culture dishes. This PIPAAm-grafted surface exhibited Hydrophobic surface properties at temperatures over the LCST and hydrophilic surface properties below the LCST. Endothelial cells and hepatocytes attached and proliferated on PIPAAm-grafted surfaces at 37 degrees C, above the LCST. The cultured cells were readily detached from these surfaces by lowering the incubation temperature without the usual damage associated with trypsinization. In this case, the optimum temperature for cell detachment was 10 degrees C for hepatocytes and 20 degrees C for endothelial cells. Cell detachment was partially inhibited by sodium azide treatment, suggesting that cell metabolism directly affects cell detachment. Morphological changes of the adherent cells during cell detachment experiments indicated further involvement of active cellular metabolic processes. Cells detached from Hydrophobic-hydrophilic PIPAAm surfaces not only via reduced cell-surface interactions caused by the spontaneous hydration of grafted PIPAAm chains, but also by active cell morphological changes which were a function of cell metabolism.
Teruo Okano - One of the best experts on this subject based on the ideXlab platform.
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mechanism of cell detachment from temperature modulated hydrophilic Hydrophobic Polymer surfaces
Biomaterials, 1995Co-Authors: Teruo Okano, Noriko Yamada, Minako Okuhara, Hideaki Sakai, Yasuhisa SakuraiAbstract:Abstract Poly( N -isopropylacrylamide) (PIPAAm), exhibiting a lower critical solution temperature (LCST) at 25 °C in physiological phosphate buffered saline solution (pH 7.4) and at 32 ° C in pure water, was grafted onto the surfaces of commercial polystyrene cell culture dishes. This PIPAAm-grafted surface exhibited Hydrophobic surface properties at temperatures over the LCST and hydrophilic surface properties below the LCST. Endothelial cells and hepatocytes attached and proliferated on PIPAAmgrafted surfaces at 37 ° C, above the LCST. The cultured cells were readily detached from these surfaces by lowering the incubation temperature without the usual damage associated with trypsinization. In this case, the optimum temperature for cell detachment was 10 ° C for hepatocytes and 20 ° C for endothelial cells. Cell detachment was partially inhibited by sodium azide treatment, suggesting that cell metabolism directly affects cell detachment. Morphological changes of the adherent cells during cell detachment experiments indicated further involvement of active cellular metabolic processes. Cells detached from Hydrophobic-hydrophilic PIPAAm surfaces not only via reduced cell surface interactions caused by the spontaneous hydration of grafted PIPAAm chains, but also by active cell morphological changes which were a function of cell metabolism.
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mechanism of cell detachment from temperature modulated hydrophilic Hydrophobic Polymer surfaces
Biomaterials, 1995Co-Authors: Teruo Okano, Noriko Yamada, Minako Okuhara, Hideaki Sakai, Yasuhisa SakuraiAbstract:Poly(N-isopropylacrylamide) (PIPAAm), exhibiting a lower critical solution temperature (LCST) at 25 degrees C in physiological phosphate buffered saline solution (pH 7.4) and at 32 degrees C in pure water, was grafted onto the surfaces of commercial polystyrene cell culture dishes. This PIPAAm-grafted surface exhibited Hydrophobic surface properties at temperatures over the LCST and hydrophilic surface properties below the LCST. Endothelial cells and hepatocytes attached and proliferated on PIPAAm-grafted surfaces at 37 degrees C, above the LCST. The cultured cells were readily detached from these surfaces by lowering the incubation temperature without the usual damage associated with trypsinization. In this case, the optimum temperature for cell detachment was 10 degrees C for hepatocytes and 20 degrees C for endothelial cells. Cell detachment was partially inhibited by sodium azide treatment, suggesting that cell metabolism directly affects cell detachment. Morphological changes of the adherent cells during cell detachment experiments indicated further involvement of active cellular metabolic processes. Cells detached from Hydrophobic-hydrophilic PIPAAm surfaces not only via reduced cell-surface interactions caused by the spontaneous hydration of grafted PIPAAm chains, but also by active cell morphological changes which were a function of cell metabolism.
Carlos Drummond - One of the best experts on this subject based on the ideXlab platform.
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Spontaneous Structuration of Hydrophobic Polymer Surfaces in Contact with Salt Solutions
Polymer Surfaces in Motion, 2015Co-Authors: Igor Sîretanu, Jean-paul Chapel, Hassan Saadaoui, Carlos DrummondAbstract:It has been described in previous chapters how spontaneous instabilities related to interfacial phenomena can be used to produce controlled patterns on Polymer surfaces. Strategies of Polymer patterning assisted by dewetting or water drop condensation were described. In this chapter we present a waterborne process based on the interaction between ions in water and Hydrophobic Polymer surfaces, modulated by the gases dissolved in the aqueous phase. We show how by controlling this interaction the Polymer surface can be conveniently modified. In the first section of the chapter we describe some aspects of the interface between water and a Hydrophobic surface. We then describe how the composition of the aqueous phase can have important consequences on the morphology of the Hydrophobic surface, and then illustrate how this process can be conveniently used to modify the morphology of a Hydrophobic Polymer in a controlled manner.
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Ions-induced nanostructuration: effect of specific ionic adsorption on Hydrophobic Polymer surfaces.
Journal of Physical Chemistry B, 2013Co-Authors: Igor Sîretanu, Jean-paul Chapel, Delfi Bastos-gonzález, Carlos DrummondAbstract:The effect of surface charges on the ionic distribution in close proximity to an interface has been extensively studied. On the contrary, the influence of ions (from dissolved salts) on deformable interfaces has been barely investigated. Ions can adsorb from aqueous solutions on Hydrophobic surfaces, generating forces that can induce long-lasting deformation of glassy Polymer films, a process called ion-induced Polymer nanostructuration, IPN. We have found that this process is ion-specific; larger surface modifications are observed in the presence of water ions and Hydrophobic and amphiphilic ions. Surface structuration is also observed in the presence of certain salts of lithium. We have used streaming potential and atomic force microscopy to study the effect of dissolved ions on the surface properties of polystyrene films, finding a good correlation between ionic adsorption and IPN. Our results also suggest that the presence of strongly hydrated lithium promotes the interaction of anions with polystyrene surfaces and more generally with Hydrophobic Polymer surfaces, triggering then the IPN process.
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Water-ions induced nanostructuration of Hydrophobic Polymer surfaces.
ACS nano, 2011Co-Authors: Igor Sîretanu, Jean-paul Chapel, Carlos DrummondAbstract:When Hydrophobic surfaces are in contact with water in ambient conditions a layer of reduced density is present at the interface, preventing the intimate contact between the two phases. Reducing the extent of this layer by degassing the water can have remarkable implications for the interaction between the two phases. The enhanced proximity between a Hydrophobic Polymer film and an aqueous solution can induce a self-assembled nanostructure on the solid surface through the development of an electro-hydrodynamic instability, due to the adsorption of the water-ions (hydronium and hydroxyl) at the interface. The self-assembled structure spontaneously relaxes back to the original flat morphology after few weeks at room temperature. This instability and the self-assembled structure are controlled by the Hydrophobic surface charge, which is determined by the pH of the aqueous phase, and by the amount of gas dissolved. This effect can be easily adjusted to modify different Hydrophobic Polymeric substrates at the submicrometer level, opening pathways for producing controlled patterns at the nanoscale in a single simple waterborne step.
Hideaki Sakai - One of the best experts on this subject based on the ideXlab platform.
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mechanism of cell detachment from temperature modulated hydrophilic Hydrophobic Polymer surfaces
Biomaterials, 1995Co-Authors: Teruo Okano, Noriko Yamada, Minako Okuhara, Hideaki Sakai, Yasuhisa SakuraiAbstract:Abstract Poly( N -isopropylacrylamide) (PIPAAm), exhibiting a lower critical solution temperature (LCST) at 25 °C in physiological phosphate buffered saline solution (pH 7.4) and at 32 ° C in pure water, was grafted onto the surfaces of commercial polystyrene cell culture dishes. This PIPAAm-grafted surface exhibited Hydrophobic surface properties at temperatures over the LCST and hydrophilic surface properties below the LCST. Endothelial cells and hepatocytes attached and proliferated on PIPAAmgrafted surfaces at 37 ° C, above the LCST. The cultured cells were readily detached from these surfaces by lowering the incubation temperature without the usual damage associated with trypsinization. In this case, the optimum temperature for cell detachment was 10 ° C for hepatocytes and 20 ° C for endothelial cells. Cell detachment was partially inhibited by sodium azide treatment, suggesting that cell metabolism directly affects cell detachment. Morphological changes of the adherent cells during cell detachment experiments indicated further involvement of active cellular metabolic processes. Cells detached from Hydrophobic-hydrophilic PIPAAm surfaces not only via reduced cell surface interactions caused by the spontaneous hydration of grafted PIPAAm chains, but also by active cell morphological changes which were a function of cell metabolism.
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mechanism of cell detachment from temperature modulated hydrophilic Hydrophobic Polymer surfaces
Biomaterials, 1995Co-Authors: Teruo Okano, Noriko Yamada, Minako Okuhara, Hideaki Sakai, Yasuhisa SakuraiAbstract:Poly(N-isopropylacrylamide) (PIPAAm), exhibiting a lower critical solution temperature (LCST) at 25 degrees C in physiological phosphate buffered saline solution (pH 7.4) and at 32 degrees C in pure water, was grafted onto the surfaces of commercial polystyrene cell culture dishes. This PIPAAm-grafted surface exhibited Hydrophobic surface properties at temperatures over the LCST and hydrophilic surface properties below the LCST. Endothelial cells and hepatocytes attached and proliferated on PIPAAm-grafted surfaces at 37 degrees C, above the LCST. The cultured cells were readily detached from these surfaces by lowering the incubation temperature without the usual damage associated with trypsinization. In this case, the optimum temperature for cell detachment was 10 degrees C for hepatocytes and 20 degrees C for endothelial cells. Cell detachment was partially inhibited by sodium azide treatment, suggesting that cell metabolism directly affects cell detachment. Morphological changes of the adherent cells during cell detachment experiments indicated further involvement of active cellular metabolic processes. Cells detached from Hydrophobic-hydrophilic PIPAAm surfaces not only via reduced cell-surface interactions caused by the spontaneous hydration of grafted PIPAAm chains, but also by active cell morphological changes which were a function of cell metabolism.
Minako Okuhara - One of the best experts on this subject based on the ideXlab platform.
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mechanism of cell detachment from temperature modulated hydrophilic Hydrophobic Polymer surfaces
Biomaterials, 1995Co-Authors: Teruo Okano, Noriko Yamada, Minako Okuhara, Hideaki Sakai, Yasuhisa SakuraiAbstract:Abstract Poly( N -isopropylacrylamide) (PIPAAm), exhibiting a lower critical solution temperature (LCST) at 25 °C in physiological phosphate buffered saline solution (pH 7.4) and at 32 ° C in pure water, was grafted onto the surfaces of commercial polystyrene cell culture dishes. This PIPAAm-grafted surface exhibited Hydrophobic surface properties at temperatures over the LCST and hydrophilic surface properties below the LCST. Endothelial cells and hepatocytes attached and proliferated on PIPAAmgrafted surfaces at 37 ° C, above the LCST. The cultured cells were readily detached from these surfaces by lowering the incubation temperature without the usual damage associated with trypsinization. In this case, the optimum temperature for cell detachment was 10 ° C for hepatocytes and 20 ° C for endothelial cells. Cell detachment was partially inhibited by sodium azide treatment, suggesting that cell metabolism directly affects cell detachment. Morphological changes of the adherent cells during cell detachment experiments indicated further involvement of active cellular metabolic processes. Cells detached from Hydrophobic-hydrophilic PIPAAm surfaces not only via reduced cell surface interactions caused by the spontaneous hydration of grafted PIPAAm chains, but also by active cell morphological changes which were a function of cell metabolism.
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mechanism of cell detachment from temperature modulated hydrophilic Hydrophobic Polymer surfaces
Biomaterials, 1995Co-Authors: Teruo Okano, Noriko Yamada, Minako Okuhara, Hideaki Sakai, Yasuhisa SakuraiAbstract:Poly(N-isopropylacrylamide) (PIPAAm), exhibiting a lower critical solution temperature (LCST) at 25 degrees C in physiological phosphate buffered saline solution (pH 7.4) and at 32 degrees C in pure water, was grafted onto the surfaces of commercial polystyrene cell culture dishes. This PIPAAm-grafted surface exhibited Hydrophobic surface properties at temperatures over the LCST and hydrophilic surface properties below the LCST. Endothelial cells and hepatocytes attached and proliferated on PIPAAm-grafted surfaces at 37 degrees C, above the LCST. The cultured cells were readily detached from these surfaces by lowering the incubation temperature without the usual damage associated with trypsinization. In this case, the optimum temperature for cell detachment was 10 degrees C for hepatocytes and 20 degrees C for endothelial cells. Cell detachment was partially inhibited by sodium azide treatment, suggesting that cell metabolism directly affects cell detachment. Morphological changes of the adherent cells during cell detachment experiments indicated further involvement of active cellular metabolic processes. Cells detached from Hydrophobic-hydrophilic PIPAAm surfaces not only via reduced cell-surface interactions caused by the spontaneous hydration of grafted PIPAAm chains, but also by active cell morphological changes which were a function of cell metabolism.
