PhD Studentship: The long, the short and the sticky: finding the mass of natural polymers by NMR

Primary Supervisor: Dr. Matthew Wallace(opens in a new window)

Polymers extracted from natural sources are ubiquitous in modern life, from texturing agents in foods to cell encapsulants in biomedicine. In addition to the structure and sequence of the monomers, the molecular mass i.e. chain length of polymers is crucial in determining their performance in these applications. However, mass determination of natural polymers is extremely difficult due to the tendency of the chains to self-associate and form gels, even at low concentrations. Common techniques such as size-exclusion chromatography assume polymer molecules behave as non-associating spheres. However, aggregation can severely distort measurements and irreversibly contaminate expensive equipment. Our inability to determine polymer molecular mass severely hinders our ability to use natural polymers for targeted applications, where extraction and processing steps must be carefully designed to obtain the correct mass fractions and properties.

In this project, you will develop and apply advanced nuclear magnetic resonance (NMR) methods to determine the chain length and aggregation state of a range of natural polymers, including those extracted from seaweed by our industrial partner. Through advanced experimental and pulse sequence design, in collaboration with Dr Rob Evans (UoManchester), you will develop first-of-their-kind models linking the Brownian motion of polymers with their macroscopic diffusion along concentration gradients at high dilution. You will thus create a unique toolset for the self-consistent determination of the overall mass distribution that could be extended to other aggregation-prone macromolecular systems such as synthetic nanoparticles for cancer therapy. Your work will provide a turning point in our ability to characterise macromolecular sizes by NMR, overcoming critical limitations of chromatographic approaches and current NMR methods that consider Brownian motion (self-diffusion) alone.

Training: You will develop a diverse and highly competitive skillset spanning NMR spectroscopy, mathematical modelling, data analysis and complementary analytical techniques including dynamic light scattering and chromatography.

Entry Requirements

The minimum entry requirement is a 2:1 Bachelor's degree in Chemistry, Pharmacy, Pharmacology, Physics, or a related discipline.

Mode of Study

Full time

Start Date

1 October 2027

Additional Funding Information

This PhD project is in a competition for a Faculty of Science funded studentship. Funding is available to UK applicants and comprises ‘home’ tuition fees and an annual stipend for 3 years. The current UEA / institutional PhD stipend rate is £21,805 and will be subject to any agreed inflationary uplift for 2027/28.