This 3-year University Research Excellence Award (REA) PhD studentship in collaboration with the Cambridge Crystallographic Data Centre aims to develop models of compression of pharmaceutically relevant materials under the pressure conditions observed in the tabletting process. This project will cover a broad range of experimental and data science techniques so that we gain a fundamental understanding of the impact of pressure from the molecular to the macro-scale.
Background and Motivation: Pressure is a valuable tool in the assessment of the solid-state forms of organic materials. It has been repeatedly demonstrated that pressure can enable the isolation of new solid-state forms of pharmaceuticals, amino acids, energetic materials as well as other types of materials such as metal-organic frameworks. This project is aligned to the EPSRC funded ‘Pressure-Induced Nucleation for the Continuous Manufacture of Supramolecular Assemblies’, where pressure is used to isolate new multi-component materials for use as seeds in ambient pressure crystallisations. The pressures that have been used to date are generally in excess of 5000 atmospheres, which is far beyond the pressure regime of a tabletting press. However, there is evidence, even at pressures between 0-1500 bar, that the structure of materials may change in ways that have the potential to affect their macroscopic properties. For example, we have evidence that mefenamic acid converts between polymorphs with pressure of manual grinding. Glycolide, a pre-cursor to the pharmaceutical polymer poly(glycolic acid), undergoes a phase transition at 1500 bar to a recoverable metastable phase.
This Project: This PhD program will investigate changes that occur in pharmaceutically relevant materials under conditions similar to those in the tabletting press. We will investigate the hydrostatic and non-hydrostatic regime using X-ray and neutron diffraction as well as Raman, IR and Terahertz spectroscopies to elucidate the structural changes that occur in a range of materials from active pharmaceutical ingredients to excipients such as fillers and glidants. The different compression regimes will allow a more complete understanding of the response of these materials under lower, more industrially relevant pressures. As part of the project there will be opportunities to travel and conduct experiments at Central Facilities such as Diamond Light Source and ISIS Neutron and Muon Source, and to interact with world-leading instrument scientists to maximise the impact of the work. The interaction with the Cambridge Crystallographic Data Centre will enable the extraction of information from these extensive experimental datasets to begin understand how the structures (from molecular to macroscopic level) are impacted by tabletting pressures and, in the long term, predict how a material and its properties will change under these conditions.
Environment: This is an exciting opportunity for the successful candidate to work alongside the world-leading EPSRC Future Continuous Manufacturing and Advanced Crystallisation Centre (CMAC, http://www.cmac.ac.uk
) within the University of Strathclyde (Glasgow, UK). This will give you access to a dedicated national network of world-class, state-of-the-art facilities, including the £34M UK-RPIF funded CMAC National Facility. There will also be the opportunity for a secondment to the Cambridge Crystallographic Data Centre. CCDC has a vibrant PhD program with affiliations to multiple Universities across the United Kingdom and beyond. They hold an annual meeting to bring the students together to encourage cross-collaboration and ideas sharing. The meeting typically brings the student into contact with other students as well as academic and industrial partners of the CCDC and can help a student form relationships and connections for their career after their PhD. The successful candidate will have the opportunity to take part in this program.
Academic and industrial supervisors:
- Dr Iain Oswald (University of Strathclyde) is an expert in diffraction and high pressure science. Main academic supervisor.
- Dr Daniel Markl (University of Strathclyde) is an expert in the monitoring of tablet disintegration and studying the microstructure of pharmaceutical drug products.
- Dr Andy Maloney (CCDC) is an expert in data science, solid form informatics and particle informatics. Main external supervisor
Applicants should send a CV, the contact details of 2 references (including email addresses) and a covering letter, explaining why the applicant wishes to carry out this project, all in one pdf document by email (Dr Iain Oswald).
This project is fully funded by University of Strathclyde and The Cambridge Crystallographic Data Centre. In addition students are also registered for the PGCert Programme, which is a supplementary qualification that develops a student’s skills, networks and career prospects.
Applicants must have obtained, or expect to obtain, a first or 2.1 UK honours degree, or equivalent for degrees obtained outside the UK, in physics, chemistry, or chemical engineering. Home/EU candidates are fully funded however international candidates may apply but will have to indicate how the difference in fees will be covered.
1. Connor, Lauren E.; Vassileiou, Antony D.; Halbert, Gavin W.; Johnston, Blair F.; Oswald, Iain D.H. CrystEngComm, 2019, Vol. 21, No. 30, 4465.
2. Hutchison, Ian; Bull, Craig L.; Marshall, William G.; Urquhart, Andrew J.; Oswald, Iain D.H. Molecules, 2019, Vol. 24, No. 11, 2174.
3. Bhardwaj, Rajni M.; McMahon, Jennifer A.; Nyman, Jonas; Price, Louise S.; Konar, Sumit; Oswald, Iain D. H.; Pulham, Colin R.; Price, Sarah L.; Reutzel-Edens, Susan M. Journal of the American Chemical Society, 2019, Vol. 141, No. 35, 13887.