Silane coupling reagent (3-aminopropyltriethoxysilane (APTES)) was prepared on single-crystal silicon substrates to form two-dimensional self-assembled monolayer (SAM). The terminal-NH2 groups in the film were in situ...Silane coupling reagent (3-aminopropyltriethoxysilane (APTES)) was prepared on single-crystal silicon substrates to form two-dimensional self-assembled monolayer (SAM). The terminal-NH2 groups in the film were in situ phosphorylated to -PO(OH)2 group to endow the film with good chemisorption ability. Then La-based thin films were deposited on phosphorylated APTES-SAM in order to make good use of the chemisorption ability of -PO(OH)2 groups. The thickness of the film was determined with ellipsometer, while phase transformation and surface morphology, surface energy, phase composition were analyzed by means of atomic force microscope (AFM), contact angle measurements and X-ray photoelectron spectroscopy (XPS). The results indicated that the terminal-NH2 groups could be completely transformed into desirable-PO(OH)2 groups after phosphorylation of APTES-SAM. Detailed XPS analysis of the La3+ peaks revealed that lanthanum element existed in the films in different states. As a result, conclusion could be made that lanthanum reacted with -PO(OH)2 groups on the surface of the substrate by chemical bond which would improve the bonding strength between the film and silicon substrate. Since the La-based thin films were well adhered to the silicon substrate, it might find promising application in the surface-modification of single-crystal Si and SiC in microelectromechanical systems (MEMS).展开更多
介孔二氧化硅SBA-16接枝含氨基的有机硅烷偶联剂APTES对于固载药物、吸附生物质及催化反应具有重要的意义。研究了SBA-16接枝γ-氨丙基-3-乙氧基硅烷(APTES)的最佳反应条件。将SBA-16高温活化后,在甲苯、异丙醇、乙腈及二甲基亚砜4种不...介孔二氧化硅SBA-16接枝含氨基的有机硅烷偶联剂APTES对于固载药物、吸附生物质及催化反应具有重要的意义。研究了SBA-16接枝γ-氨丙基-3-乙氧基硅烷(APTES)的最佳反应条件。将SBA-16高温活化后,在甲苯、异丙醇、乙腈及二甲基亚砜4种不同极性的反应介质中接枝APTES,通过XPS、FTIR、BET等手段表征了接枝前后的样品。结果表明,低极性反应介质中APTES接枝效果优于高极性反应介质,极性越小越有利于硅烷化反应。在4种反应介质中,甲苯为最佳反应溶剂。在低极性甲苯溶剂中,通过单因素实验和正交实验分析法确定SBA-16的质量为1 g,APTES用量为1 m L,反应温度为80℃,反应时间为8 h时,其相对接枝率达到最大。展开更多
The procedure to measure liposome in aqueous solution has been examined using atomic force microscope (AFM). We concluded a chemical modified silicon wafer (substrate for AFM observation of liposome) with 3-aminopropy...The procedure to measure liposome in aqueous solution has been examined using atomic force microscope (AFM). We concluded a chemical modified silicon wafer (substrate for AFM observation of liposome) with 3-aminopropyltrieth-oxysilane (APTES) which enabled us to scan anionic liposome softly in water because they were keeping structures as vesicles and stably adsorbed on the substrate by electrostatic force. From captured AFM topographic images, we counted the amount of liposome and analyzed the distribution of mean diameters, which were corrected by an approximated curve of the tip shape. We discussed the method of effective evaluation as practical analysis and its problems for robust analysis.展开更多
基金Project supported by the National Natural Science Foundation of China (50475023)
文摘Silane coupling reagent (3-aminopropyltriethoxysilane (APTES)) was prepared on single-crystal silicon substrates to form two-dimensional self-assembled monolayer (SAM). The terminal-NH2 groups in the film were in situ phosphorylated to -PO(OH)2 group to endow the film with good chemisorption ability. Then La-based thin films were deposited on phosphorylated APTES-SAM in order to make good use of the chemisorption ability of -PO(OH)2 groups. The thickness of the film was determined with ellipsometer, while phase transformation and surface morphology, surface energy, phase composition were analyzed by means of atomic force microscope (AFM), contact angle measurements and X-ray photoelectron spectroscopy (XPS). The results indicated that the terminal-NH2 groups could be completely transformed into desirable-PO(OH)2 groups after phosphorylation of APTES-SAM. Detailed XPS analysis of the La3+ peaks revealed that lanthanum element existed in the films in different states. As a result, conclusion could be made that lanthanum reacted with -PO(OH)2 groups on the surface of the substrate by chemical bond which would improve the bonding strength between the film and silicon substrate. Since the La-based thin films were well adhered to the silicon substrate, it might find promising application in the surface-modification of single-crystal Si and SiC in microelectromechanical systems (MEMS).
文摘介孔二氧化硅SBA-16接枝含氨基的有机硅烷偶联剂APTES对于固载药物、吸附生物质及催化反应具有重要的意义。研究了SBA-16接枝γ-氨丙基-3-乙氧基硅烷(APTES)的最佳反应条件。将SBA-16高温活化后,在甲苯、异丙醇、乙腈及二甲基亚砜4种不同极性的反应介质中接枝APTES,通过XPS、FTIR、BET等手段表征了接枝前后的样品。结果表明,低极性反应介质中APTES接枝效果优于高极性反应介质,极性越小越有利于硅烷化反应。在4种反应介质中,甲苯为最佳反应溶剂。在低极性甲苯溶剂中,通过单因素实验和正交实验分析法确定SBA-16的质量为1 g,APTES用量为1 m L,反应温度为80℃,反应时间为8 h时,其相对接枝率达到最大。
文摘The procedure to measure liposome in aqueous solution has been examined using atomic force microscope (AFM). We concluded a chemical modified silicon wafer (substrate for AFM observation of liposome) with 3-aminopropyltrieth-oxysilane (APTES) which enabled us to scan anionic liposome softly in water because they were keeping structures as vesicles and stably adsorbed on the substrate by electrostatic force. From captured AFM topographic images, we counted the amount of liposome and analyzed the distribution of mean diameters, which were corrected by an approximated curve of the tip shape. We discussed the method of effective evaluation as practical analysis and its problems for robust analysis.
