In-situ Microstructural Characterization of the Biodegradation of Polyhydroxyalkanoates (PHAs)

聚羟基脂肪酸酯 (PHA) 生物降解的原位微观结构表征

• 批准号: 0071717
• 负责人: Brian Augustine
• 金额: $ 21万
• 依托单位: James Madison University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-04-01 至 2004-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0071717&HistoricalAwards=false
• 关键词: situ; Microstructural; Characterization; Biodegradation; Polyhydroxyalkanoates

The objective of this study is to investigate the in-situ and real-time enzymatic biodegradation of the surface microstructure in thin films of polyhydroxyalkanoates (PHAs), and correlate these changes with the degradation mechanism. In-situ surface microstructural changes will be monitored using the liquid cell capability of the atomic force microscope (AFM) and will be performed at elevated temperatures to maximize the enzymatic activity of the depolymerase. Literature has suggested that biodegradation preferentially occurs in amorphous regions of bulk copolymers opposed to crystalline regions. However, this postulate has never been analytically confirmed. This theory will be evaluated using the phase imaging capability of the AFM and confirmed with surface analytical spectroscopy. A secondary objective of this project is to better understand the role of surface chemistry in the microfabrication of biomaterials surfaces/ Through control of surface chemistry via hydrophobic and hydrophilic modifications to the substrate, novel patterning techniques for PHAs using microcontact printing (m-CP) of alkanethiol self-assembled monolayers (SAMs) to gold surfaces will be studied. This will be used to produce a self-aligned thin film internal height standard for the in-situ surface microstructural changes and bulk mechanical properties will initiated. A final objective of this project is the scientific training of undergraduate research students and high school science teachers in an interdisciplinary research project.This project will provide a new insight into the breakdown mechanism in an important class biodegradable plastics. It is an interdisciplinary project for undergraduate research students and high school teachers at the interface between the biological and materials sciences. Future scientists and present secondary school teachers in chemistry, biology and materials science need to be trained in the complex interactions of these disciplines as this project highlights.

本研究的目的是研究聚羟基烷酸(PHAs)薄膜表面微结构的原位和实时酶生物降解，并将这些变化与降解机理相关联。原位表面微结构变化将使用原子力显微镜(AFM)的液体细胞能力进行监测，并将在高温下进行，以最大限度地提高去聚合酶的酶活性。文献表明，生物降解优先发生在本体共聚物的无定形区域，而不是结晶区。然而，这一假设从未得到分析上的证实。这一理论将使用原子力显微镜的相位成像能力进行评估，并通过表面分析光谱进行验证。该项目的第二个目标是更好地了解表面化学在生物材料表面微制造中的作用/通过对衬底进行疏水和亲水修饰来控制表面化学，将研究使用烷硫醇自组装单分子膜(SAM)到金表面的微接触印刷(m-CP)的新型PHAs图案化技术。这将被用来制作一种自对准薄膜内部高度标准，用于原位改变表面微结构和块体力学性能。这个项目的最终目标是对本科生和高中科学教师进行跨学科研究项目的科学培训。这个项目将为一门重要的可生物降解塑料的分解机制提供新的见解。它是一个跨学科的项目，面向生物科学和材料科学之间的本科生和高中教师。正如该项目所强调的那样，未来的科学家和现在的中学化学、生物和材料科学教师需要接受这些学科之间复杂相互作用的培训。