Design, Synthesis and Application of Chemically Fuelled Molecular Machines

Abstract

Artificial molecular machines mimic the exquisite functions of biological motors like ATP synthase and kinesin. They mostly operate through ratchet mechanisms, providing powerful tools for manipulating matter at the molecular level. Chemically fuelled molecular machines enable programmable mechanical tasks by harnessing the chemical energy from catalysed fuel to waste reactions. This thesis describes the design, synthesis and applications of a series of synthetic chemically fuelled molecular machines, which are important to deepen our understanding of how molecular machines transduce energy across length scales and develop artificial molecular nanotechnology. Chapter One summarises the development of artificial molecular machines, mainly molecular ratchets, highlighting their applications in harnessing energy from chemical reactions or light to perform mechanical work. Chapter Two demonstrates the first experimental transduction of chemical energy into mechanical work through catalysis by synthetic catalysis-driven motors covalently embedded in polymer gels. Chapter Three introduces a dual coaxial contra-rotating molecular rotary motor, achieving record rotational speeds of 0.43 rpm while maintaining high fuel efficiency (>90%). Chapter Four explores the synthesis of peptide-based rotaxanes positional isomers with tunable stability and secondary structures for bio-integrated molecular machines.

Date of Award	23 May 2025
Original language	English
Awarding Institution	The University of Manchester
Supervisor	David Leigh (Main Supervisor) & Robert Dryfe (Co Supervisor)