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

James Madison University, Harrisonburg VA

Investigators

Abstract

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.