Dissipative Vesicle Assemblies Driven by Chemical Fuels

With the support of the Macromolecular, Supramolecular and Nanochemistry (MSN) Program in the Division of Chemistry, Professor Neal Devaraj of the University of California, San Diego will develop chemistries for generating dissipative phospholipid vesicles that exist far from equilibrium and are driven and sustained by the provision of chemical coupling agents (chemical fuels). A phospholipid vesicle, also known as a liposome, is a spherical structure made up of a phospholipid bilayer, which forms a closed container that can encapsulate various substances such as drugs or nutrients. This work will study dissipative phospholipid assemblies that are self-organized, dynamic structures that continuously consumes energy from chemical fuels to maintain their structure and function. This project will also support the creation of an educational outreach component aimed at introducing the principles of chemistry and self-assembly to high school students with backgrounds underrepresented in the sciences. This project will develop and characterize dissipative lipid assemblies and explore the role of chemical fuel addition on the formation, chemical composition, and properties of the generated supramolecular structures. While energetically costly, dependence on chemical fuel can endow supramolecular lipid assemblies with the ability to regulate the size and morphology of the structures formed to rapidly respond and adapt to external stimuli. If successful, this project will enable us to better understand the molecular underpinnings of supramolecular self-assembly for generating dynamic lipid systems with tunable size, shape, and properties. The knowledge gained from these studies will also shed light on the fundamental benefit and drawbacks of maintaining nonequilibrium assembled states in lipid systems, and will facilitate the construction of functional lipid materials with adaptive behaviors. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.