Dissertation defence (Biotechnology): MSc Juuso Pohjola
Time
28.11.2025 12.00 – 16.00
MSc Juuso Pohjola defends the dissertation in Biotechnology titled “Additive manufacturing of polymer-based drug delivery systems: Effects of semi-solid ink composition and manufacturing process parameters on structural and drug release properties” at the University of Turku on 28 November 2025 at 12.00 (University of Turku, Medisiina C, Osmo Järvi lecture hall, Kiinamyllynkatu 10, Turku). Lectio precursoria will be in Finnish.
Opponent: Professor Hélder A. Santos (University of Groningen, the Netherlands)
Custos: Professor Tero Soukka (University of Turku)
Doctoral Dissertation at UTUPub: https://urn.fi/URN:ISBN:978-952-02-0387-0
***
Summary of the Doctoral Dissertation:
Controlled release drug delivery systems improve treatment efficacy and reduce side effects by releasing drugs gradually over an extended period. However, these systems need further customization to meet the unique needs of individual patients. Semi-solid extrusion (SSE) 3D printing has emerged as a promising technology in the pharmaceutical field, allowing for the customization of product size, shape, and drug release properties.
This dissertation explores the potential of SSE 3D printing to create polymer-based drug delivery systems designed for the long-term release of macromolecule drugs, a topic that has received less attention in recent research. To achieve this, biodegradable polymer microspheres were combined with a hydrogel to form printable inks. These inks were studied to understand their properties and behavior in the printing process. A solvent-based post-processing method was developed to fuse the microspheres together in the printed samples. Finally, drug delivery systems were printed using inks containing microspheres loaded with a model drug, and drug release studies were conducted.
The results showed that the microsphere concentration in the ink affected its flow properties and behavior in the printing process. One key finding was the extrudate swell phenomenon, the deposited filament had a diameter larger than the nozzle. This was identified as an important factor to quantify and address during 3D printing process optimization. The drug release tests revealed that the rate of release could be controlled by adjusting the ink composition and the post-processing step, allowing for drug release over a period of up to three months.
Overall, the studies demonstrated the feasibility of SSE 3D printing for manufacturing controlled release drug delivery systems for macromolecule drugs, supporting the future development of personalized medicine.
Opponent: Professor Hélder A. Santos (University of Groningen, the Netherlands)
Custos: Professor Tero Soukka (University of Turku)
Doctoral Dissertation at UTUPub: https://urn.fi/URN:ISBN:978-952-02-0387-0
***
Summary of the Doctoral Dissertation:
Controlled release drug delivery systems improve treatment efficacy and reduce side effects by releasing drugs gradually over an extended period. However, these systems need further customization to meet the unique needs of individual patients. Semi-solid extrusion (SSE) 3D printing has emerged as a promising technology in the pharmaceutical field, allowing for the customization of product size, shape, and drug release properties.
This dissertation explores the potential of SSE 3D printing to create polymer-based drug delivery systems designed for the long-term release of macromolecule drugs, a topic that has received less attention in recent research. To achieve this, biodegradable polymer microspheres were combined with a hydrogel to form printable inks. These inks were studied to understand their properties and behavior in the printing process. A solvent-based post-processing method was developed to fuse the microspheres together in the printed samples. Finally, drug delivery systems were printed using inks containing microspheres loaded with a model drug, and drug release studies were conducted.
The results showed that the microsphere concentration in the ink affected its flow properties and behavior in the printing process. One key finding was the extrudate swell phenomenon, the deposited filament had a diameter larger than the nozzle. This was identified as an important factor to quantify and address during 3D printing process optimization. The drug release tests revealed that the rate of release could be controlled by adjusting the ink composition and the post-processing step, allowing for drug release over a period of up to three months.
Overall, the studies demonstrated the feasibility of SSE 3D printing for manufacturing controlled release drug delivery systems for macromolecule drugs, supporting the future development of personalized medicine.
University Communications