Ph.D. position available: Stability of Pharmaceutical Suspensions

A Ph.D. position within formulation characterization focused on stability investigations of pharmaceutical suspensions is available at the Department of Physics, Chemistry, and Pharmacy in the pharmacy research group.

Project background

Terminal sterilization is the process of sterilizing a pharmaceutical product in its final container. Among various sterilization techniques, moist heat sterilization (autoclaving at 121°C) is the most widely accepted and validated method due to its proven microbial lethality, cost-effectiveness, and ease of implementation at scale- Other options are gamma radiation and E-beam. Regulatory agencies, including the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA), strongly prefer terminal sterilization over aseptic manufacturing wherever feasible, as it offers a higher Sterility Assurance Level (SAL) and significantly reduces the risk of post-process contamination.

Despite its advantages, terminal sterilization is not universally applicable. A significant limitation arises when drug substances or drug formulations are thermolabile, meaning they degrade either chemically or physically upon exposure to high temperatures. This is especially problematic for colloidal based formulations, such as suspensions intended for injection, which also cannot be sterile filtrated. Terminal sterilization of suspensions can lead to aggregation, hydrolysis, oxidation, Ostwald riepening or other chemical and physical degradation pathways. As a result, most marketed parenteral suspension products are manufactured using aseptic processing, where the drug and container are sterilized separately and then combined under aseptic conditions. Although effective, aseptic processing introduces significant operational complexity, requires extensive environmental controls, is more costly, and presents a higher risk of microbial contamination.

To stabilize the inherently thermodynamic instable suspensions addition of surfactants to stabilize the formulation is often needed. These surfactants are commonly nonionic surfactants, such as polysorbates and poloxamers, which have cloud points below 121 °C, i.e. they will phase invert at autoclavation temperature. Older literature teaches us that the cloud point can be elevated by the addition of e.g. PEG400, PEG3350, and some lecithin’s. This was in a later study applied to suspensions with ethyl diatrizoate nanocrystalline suspensions that could be stream autoclaved if the media was added cloud point boosters to bring it to approximately 135 °C. Colleges from Pfizer have at conferences presented data suggesting that they occasionally see similar trend for some compound, however, slides have not been shared for further analysis.

This project aligns closely with Quality by Design (QbD) principles, emphasizing risk assessment, process understanding, and robust design space development. A successful outcome of this project will provide pharmaceutical scientists with the tools to improve the physical stability of aqueous suspensions and if fully successful extend the applicability of terminal sterilization of parenteral suspensions thus improving product quality, regulatory compliance, and patient safety. By overcoming formulation barriers to terminal sterilization, this project has the potential to significantly impact the field of sterile pharmaceutical manufacturing, offering both clinical and economic benefits across the product lifecycle.

Qualifications

• We are looking for a candidate with a strong interest in working on the boundary between pharmacy, chemistry and physics focused on formulation and characterization of suspensions and solid materials.
• The candidate will hold a M.Sc. in pharmacy, chemistry, physics, or closely related area.
• Previous experiences with one or more of the following are considered an advantage: formulation design of suspensions, particle size characterization, XRPD, solid stage NMR, low energy Raman microscopy.
• The candidate must be independent and fluent in English both orally and written.

For further information about the position please contact Professor René Holm ([email protected]).

The Department of Physics, Chemistry and Pharmacy is one of four departments at the Faculty of Science, SDU and is located in Odense. At the Department of Physics, Chemistry and Pharmacy, we contribute to solving some of society’s greatest challenges within energy, environment, health, and sustainability. We succeed because we build bridges between disciplines and transcend traditional boundaries. Our interdisciplinary mindset is not only a fundamental condition, but also our strength. And it is a strength that ensures our research and education are recognized both nationally and internationally.

Our vision is to create and apply knowledge across the natural sciences. We are unique in housing research within physics, chemistry, and pharmacy under one department, which provides excellent opportunities to explore the intersections between these disciplines.

Read more about the Ph.D. program at the Department.

Application, salary etc.

Appointment as a PhD Research Fellow is for three years. Employment stops automatically at the end of the period.

The successful applicant will be employed in accordance with the agreement on salaried PhD scholars between the Ministry of Finance and AC (the Danish Confederation of Professional Associations). Please check links for more information on salary (only available in Danish) and taxation.

The successful candidate will be enrolled at this university in accordance with faculty regulations and the Danish Ministerial Order on the PhD Programme at the Universities (PhD order).

Further information about the PhD-study can be found at the University’s website.

The University wishes our staff to reflect the diversity of society and thus welcomes applications from all qualified candidates regardless of personal background.

Application must be in English and made in the form of a Declaration of Interest including the following:

• A letter stating your specific interest, motivation, and qualifications for the project in question (max. two pages) .
• Detailed CV, including personal contact information and date entries
• Copies of diplomas, Bachelor as well as Master’s degree, including transcript of notes/grades.
• The names and complete contact details (phone numbers and e-mail) of at least two referees details for at least 2 referees who can vouch for your skills.

Incomplete applications and applications received after the deadline will neither be considered nor evaluated.

Shortlisting may be used as part of the assessment process, and an interview may be included in the overall evaluation of the applicant’s qualifications.

Applications must be submitted electronically using the link “Apply now”. Attached files must be in Adobe PDF format. We strongly recommend that you read How to apply for a position at SDU before you apply.

Since not all members of the appointment committee are Danish-speaking, it is recommended that your application is submitted in English.

The University wishes our staff to reflect the diversity of society and thus welcomes applications from all qualified candidates regardless of personal background.

Further information for international applicants about entering and working in Denmark can be found on the University’s website.

Application deadline: 26 December 2025

Starting date: 01 February 2026, or as soon as possible thereafter.

Location
Odense M, Denmark

Apply Before
2025-12-26T22:59:00+00:00