ChBE Seminar Series: Vijay John
Tuesday, December 2, 2014
11:00 a.m.-12:15 p.m.
Room 2108, Chemical and Nuclear Engineering Bldg.
Professor Jeffery Klauda
Using Hydrophobes in Modified Biopolymers as Hooks in Supramolecular Materials Assembly
The Leo S. Weil Professor in Engineering
Department of Chemical and Biomolecular Engineering
Our recent work is based on the hydrophobic modification of biopolymers such as chitosan to provide building blocks for supramolecular architectures. The attachment of long chain alkyl groups to the polymer backbone allows the polymer to stick to hydrophobic surfaces and to “hook” onto lipid bilayers. We therefore demonstrate how functional structures can be derived using this concept. The following are some of the applications that will be described (a) the use of hydrophobically modified chitosan (HMC) as a method to gel carbon structures in aqueous media using the carbons as nodes in a polymer network (b) the use of such polymers to capture and tether liposomes and vesicular bodies to surfaces thus generating surfaces with densely packed liposomal layers that exhibit very low coefficients of friction in sliding lubrication representative of articular joints (c) the ability of hydrophobically modified chitosan to insert it’s hydrophobes into oil drops leading to a synergistic effect with surfactants in the use of dispersants for oil spill remediation. The talk will also describe the use of hydrophobically modified self-associating biopolymer electrolytes in influencing self-assembly using both the hydrophobic effect and electrostatic interactions. Such dual non-covalent interactions can be exploited to build architectures that are multifunctional, or modulated to tune architectures for specific functionalities. This work is done in collaboration with Dr. Srini Raghavan at Maryland who pioneered the field of hydrophobically modified biopolymers.