Probing the metal surface/amino acid interface with scanning tunneling microscopy and synchrotron spectroscopy

设计用于人体的材料，例如髋关节和膝关节置换，需要对材料表面和身体组织之间的相互作用有很好的了解，以避免出现排斥等问题。解决这一复杂问题的一种方法是自下而上地在纳米尺度上研究氨基酸分子与不同表面的相互作用--单个分子的长度尺度。氨基酸是蛋白质的基础，蛋白质是大的生物分子，在我们的身体中执行许多关键功能，是身体组织的主要组成部分。了解单个氨基酸分子如何与表面相互作用的进展为构建涉及蛋白质、细胞和整个组织的更复杂相互作用的图景提供了基础。这项研究旨在研究在受控条件下，氨基酸如何与金属表面相互作用，以及当它们在金属表面时如何相互作用。特别是，我们试图了解这些相互作用如何影响氨基酸附着在表面的强度、氨基酸在表面上的位置和取向、氨基酸形成二维图案的能力以及氨基酸对环境变化的反应能力。这些目标将通过使用萨斯喀彻温省大学物理和工程物理系新的表面科学实验室和萨斯卡通的加拿大光源同步加速器提供的实验技术来实现。氨基酸将使用扫描隧道显微镜在金属表面成像，这是一种能够跟踪表面原子和单个分子轮廓的灵敏仪器。加拿大光源同步加速器的强光将被用来探测分子粘在表面的强度和位置。从这项研究中获得的关于分子-表面相互作用的知识对物理和化学以及改进的生物材料的开发都是基本感兴趣的。

The design of materials for use in the human body, for example for hip and knee replacements, requires a good understanding of the interaction between the surface of that material and the body's tissues, in order to avoid problems like rejection. One approach to solving this complex problem is to start from the bottom up and examine the interaction of amino acid molecules with different surfaces at the nanoscale - the length scale of an individual molecule. Amino acids are the building blocks of proteins, large biomolecules which perform many key functions in our bodies and are a major constituent of body tissues. Advances in understanding how individual amino acid molecules interact with a surface provide a foundation upon which to build a picture of ever more complex interactions involving proteins, cells and whole tissues.This research is designed to study, under controlled conditions, how amino acids interact with a metal surface and with each other when they are on that surface. In particular, we seek to understand how these interactions influence the strength with which the amino acids stick to the surface, the position and orientation of the amino acids on the surface, the ability of the amino acids to form two dimensional patterns, and the ability of the amino acids to respond to changes in their environment. These goals will be accomplished by using experimental techniques available in a new surface science laboratory in the Department of Physics and Engineering Physics at the University of Saskatchewan and at the Canadian Light Source synchrotron in Saskatoon. Amino acids will be imaged on metal surfaces using a scanning tunneling microscope, a sensitive instrument which is able to trace the contours of atoms and individual molecules on a surface. The bright light of the Canadian Light Source synchrotron will be used to probe how strongly and in what position the molecules stick to the surface. The knowledge of molecule-surface interactions gained from this research is of fundamental interest in physics and chemistry and also in the development of improved biomaterials.