The miscibility, stability and compressibility of L-<em>α</em> dioleoylphosphatidylcholine/rutin laurate mixed monolayer at the air/water were investigated by Langmuir film balance to reveal the character...The miscibility, stability and compressibility of L-<em>α</em> dioleoylphosphatidylcholine/rutin laurate mixed monolayer at the air/water were investigated by Langmuir film balance to reveal the characteristic of the molecular interaction. The two components of DOPC/RL mixed monolayer were miscible throughout the mixture composition range and at three experimental temperatures of 10<span style="white-space:nowrap;">°</span>C, 25<span style="white-space:nowrap;">°</span>C and 37<span style="white-space:nowrap;">°</span>C. At all experimental conditions, RL increased the compressibility and elasticity of the DOPC monolayer. Both the temperature and the composition of the membrane affected the form of intermolecular forces in the mixed monolayer.展开更多
Oligo(ethylene glycol) (-OEG) and amino (-NH2) mixed self-assembled monolayers (SAMs) were employed as model substrates to investigate the effect of charge density on the fate of mesenchymal stem cells (MSCs...Oligo(ethylene glycol) (-OEG) and amino (-NH2) mixed self-assembled monolayers (SAMs) were employed as model substrates to investigate the effect of charge density on the fate of mesenchymal stem cells (MSCs) and osteopontin (OPN) adsorption. We found that all surfaces presenting -NH2 groups favored cell responses regardless of the surface charge. Meanwhile, OPN adsorption could remain stable on the mixed SAMs over a certain range of charge densities. Our work provides some insights into cell responses and protein adsorption to surface charge.展开更多
Morphology of dipalmitoyl phosphatidyl choline (DPPC)-cholesterol (Chol) mixed monolayer formed on water surface by dropping method was investigated using surface tension measurement (STm), Brewster angle microscopy (...Morphology of dipalmitoyl phosphatidyl choline (DPPC)-cholesterol (Chol) mixed monolayer formed on water surface by dropping method was investigated using surface tension measurement (STm), Brewster angle microscopy (BAM), and fluorescence microscopy (FM). STm showed strong condensation effect of Chol in fluidic DPPC monolayer. Excess area (S<sub>ex</sub>) from mean mixing state of DPPC and Chol was about twice larger than that by general compression method in the range from xC = 0.2 to 0.4 (xC: mole fraction of Chol). BAM and FM images showed clearly that the fluidic DPPC monolayer changed to condensed rigid monolayer due to the condensation effect of Chol. At more than xC = 0.3 DPPC-Chol mixed monolayer changed to condensed state similar to the Chol monolayer. These results support previous reports by compression method that Chol molecule demonstrates the strong condensation effect to the fluidic monolayer and also indicate that dropping method enables to form unique monolayer on the water surface.展开更多
文摘The miscibility, stability and compressibility of L-<em>α</em> dioleoylphosphatidylcholine/rutin laurate mixed monolayer at the air/water were investigated by Langmuir film balance to reveal the characteristic of the molecular interaction. The two components of DOPC/RL mixed monolayer were miscible throughout the mixture composition range and at three experimental temperatures of 10<span style="white-space:nowrap;">°</span>C, 25<span style="white-space:nowrap;">°</span>C and 37<span style="white-space:nowrap;">°</span>C. At all experimental conditions, RL increased the compressibility and elasticity of the DOPC monolayer. Both the temperature and the composition of the membrane affected the form of intermolecular forces in the mixed monolayer.
基金supported by the National Basic Research Program of China(No.2012CB619100)the National Natural Science Foundation of China(No.51232002)+1 种基金the 111 Project(No.B13039)the Science and Technology Program of Guangdong Province(No.2013B010403007)
文摘Oligo(ethylene glycol) (-OEG) and amino (-NH2) mixed self-assembled monolayers (SAMs) were employed as model substrates to investigate the effect of charge density on the fate of mesenchymal stem cells (MSCs) and osteopontin (OPN) adsorption. We found that all surfaces presenting -NH2 groups favored cell responses regardless of the surface charge. Meanwhile, OPN adsorption could remain stable on the mixed SAMs over a certain range of charge densities. Our work provides some insights into cell responses and protein adsorption to surface charge.
文摘Morphology of dipalmitoyl phosphatidyl choline (DPPC)-cholesterol (Chol) mixed monolayer formed on water surface by dropping method was investigated using surface tension measurement (STm), Brewster angle microscopy (BAM), and fluorescence microscopy (FM). STm showed strong condensation effect of Chol in fluidic DPPC monolayer. Excess area (S<sub>ex</sub>) from mean mixing state of DPPC and Chol was about twice larger than that by general compression method in the range from xC = 0.2 to 0.4 (xC: mole fraction of Chol). BAM and FM images showed clearly that the fluidic DPPC monolayer changed to condensed rigid monolayer due to the condensation effect of Chol. At more than xC = 0.3 DPPC-Chol mixed monolayer changed to condensed state similar to the Chol monolayer. These results support previous reports by compression method that Chol molecule demonstrates the strong condensation effect to the fluidic monolayer and also indicate that dropping method enables to form unique monolayer on the water surface.