The development of molecular switches and machines is a vital part of the current scientific drive towards miniaturization. Appreciable advances have been made in recent years in the design of new molecular switches, integrating them into bulk materials, and applying them in new functions. However, there are still many challenges that need to be addressed before such systems can find their way into real-life applications. This research addresses one of these issues, which is the lack of a basic understanding of how to make molecular switches and machines work together towards a useful goal - a solved problem in natural biological systems. To mimic Nature, the Aprahamian research group at Dartmouth College studies the interactions of molecular switches with their environment. This knowledge may lead to the engineering of dynamic, adaptive and self-regulating molecular assemblies that can be used in drug delivery and energy-related applications. The broader impacts of this research include participation in the American Chemical Society's SEED Program and other endeavors to help retain students at different levels of education (high school, undergraduate, and graduate students) in the sciences. Professor Aprahamian also uses interactive demonstrations to educate the public about important concepts related to supramolecular chemistry. These activities are expected to strengthen and extend the group's informal and formal science education partnerships and networks with local schools and science museums.
With the support from the Macromolecular, Supramolecular and Nanochemistry Program of the Division of Chemistry, this research examines the coupling of zinc(II)-initiated, coordination-coupled, deprotonation (CCD) of hydrazone switches with other metals, particularly palladium(II). These reactions extend the capabilities of currently known switching cascades and open the way for compartmentalization driven catalysis using self-assembled cages. The Aprahamian group gains a deeper understanding of the factors that control CCD-enabled negative feedback loops and uncovers the underlying rules that lead to analyte regulation. Finally, the group develops new zinc(II) photocages/switches that can couple with CCD and feedback loops to enable the future design of oscillating systems, molecular clocks, and self-regulating assemblies.
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.
