MODIFICATION OF SURFACE REACTIVITIES ON SILICA (1000) AS MODELS OF BIOADHESION

作为生物粘附模型的二氧化硅 (1000) 表面反应性的修饰

• 批准号: 6159105
• 负责人: EARL L SMITH
• 金额: $ 4.04万
• 依托单位: UNIVERSITY OF TEXAS EL PASO
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2000-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6159105
• 关键词: X ray crystallography; adhesions; biomaterial interface interaction; chemical models; chemical reaction; gas chromatography mass spectrometry; infrared spectrometry; membrane fusion; nuclear magnetic resonance spectroscopy; organic chemicals; silicates; sulfur compounds; thioether; thiols

A study of the adhesion of organosulfur compounds at the surface of silica is proposed. This work defines a previously unknown mode of binding hydrocarbon to the surface of silica. Chemical reactions of molecules grafted on surfaces are of growing interest in surface science; these systems, characterized by IR transmission and solid state NMR, have direct relevance to bioadhesion--the physical and chemical interactions of bacteria adhering to membrane, or white blood cells adhering to bioimplants. There are four major targets: 1. New surface reactions on Silica (100012). We will react organosulfur compounds with the surface of silica heated to 1000C in high vacuum. For example, a thiol gives a thiosiloxane film containing the S-Si bond. 2.Surface Grafting of Bifunctional Molecules on Silica (1000). Bifunctional molecules, containing the organosulfur head group to react with the silica (1000) and a terminal functional group exposed at the surface will be grafted. The second functionality must either not react with the silica (1000) or be chemically protected from such reaction. For example, in a bifunctional molecule such as a halogenated alkanethiol, Cl-(CH2)nSH, both the S and the Cl could potentially interact with surface siloxanes. Trifunctional cysteine could be absorbed exclusive through its SH group by protecting the carboxylate through esterification and the amine through alkylation. 3. In-situ reactions. The goal is to prepare surface functionalities which could not be prepared directly from absorption of bifunctional molecules. Dealkylation and hydrolysis of protected groups referred to in 2 above will be the first experiments. Another examine would be preparation of an aldehyde terminated thiosiloxane film; the adsorbate precursor C=O (CH2)nSH is synthetically inaccessible. This firm may weakly coordinate /adhere metals. 4. Adsorbate-Interactions with the Modified Surfaces. Studies of the molecular environment at the interface reveal the fundamental factors affecting surface-adsorbate interactions. We will vary systematically the alkyl chain length and the chain terminus to effect steric and chemical control of the surface's absorption properties. These effects will be probed with spectroscopic studies of controlled atmosphere environments such as e.g. reversible pyridine coordination.

提出了有机硫化合物在二氧化硅表面的粘附的研究。这项工作定义了以前未知的结合烃与二氧化硅表面结合的模式。在表面科学中，移植在表面上的分子的化学反应越来越感兴趣。这些系统以IR传播和固态NMR为特征，与生物粘附具有直接相关性 - 粘附在膜上的细菌的物理和化学相互作用，或粘附在生物植物上的白细胞。有四个主要目标：1。二氧化硅上的新表面反应（100012）。我们将在高真空中反应有机硫化合物与二氧化硅表面的反应。例如，硫醇给出了含有S-SI键的硫代硅氧烷膜。 2.二氧化硅上双功能分子的表面接枝（1000）。双功能分子，其中包含有机硫的头组与二氧化硅反应（1000）和暴露于表面的末端官能团。第二个功能必须与二氧化硅（1000）反应或化学保护这种反应。例如，在双功能分子中，例如卤代烷硫醇，Cl-（CH2）NSH，S和CL都可能与表面硅氧烷相互作用。三官能半胱氨酸可以通过其SH组通过酯化和通过烷基化保护羧酸盐来吸收独家。 3。原位反应。目的是准备表面功能，这些功能无法直接从双功能分子的吸收中制备。上述2中提到的受保护组的交易甲基化和水解将是第一个实验。另一个检查是准备醛终止硫硅氧烷膜。吸附剂前体C = O（CH2）NSH是综合无法访问的。该公司可能会弱协调 /粘附金属。 4。与修饰表面的吸附物相互作用。界面上分子环境的研究揭示了影响表面吸附物相互作用的基本因素。我们将系统地改变烷基链长度和链末端，以实现表面吸收特性的空间和化学控制。这些影响将通过对控制大气环境（例如可逆的吡啶协调。