Structural and functional characterisation of 3D printed pharmaceutical dosage forms

Poster presented on ToScA 2018 - Award winning lighting talk
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Orestis L. Katsamenis ^1* , Christos I. Gioumouxouzis ² , Nikolaos Bouropoulos ^3,4 , Dimitrios G. Fatouros ²

^{1 μ-VIS X-Ray Imaging Centre, Faculty of Engineering and the Environment, University of Southampton, SO17 1BJ Southampton, UK;
2 Laboratory of Pharmaceutical Technology, School of Pharmacy, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Hellas;
3 Department of Materials Science, University of Patras, 26504 Rio, Patras, Hellas;
4 Foundation for Research and Technology Hellas, Institute of Chemical Engineering and High Temperature Chemical Processes, Patras, Hellas}

Fused filament fabrication (FFF) three-dimensional (3D) printing, a method used to produce objects in three-dimensional space by sequential deposition of layers of material, is being steadily deployed as manufacturing technology for the development of personalized pharmaceutical dosage forms. This technology enables production of dosage forms with complex geometries, allowing manufacturers to improve on pharmacokinetics and/or more accurately target delivery sites. This can be achieved either by incorporating pharmaceutically active substances into polymeric filaments used to 3D print the dosage form, or by 3D printing complex carriers (excipients) which encapsulate the drug for controlled delivery.

The adoption of 3D printing technology by pharmaceutical industry and research, created a need for alternative techniques able to characterise increasingly complex dosage form geometries. Here we demonstrate the use of such technology, namely X-ray microfocus computed tomography (μCT, micro-CT), to characterise in-house designed and 3D printed pharmaceutical formulations. The non-destructive high-resolution 3D (volume) imaging capabilities of μCT allowed us to conduct a wide range of characterisation studies. Specifically: [a] structural integrity of the 3D printed object by means of defect analysis; [b] quality control of the fabrication process accuracy by means of actual / nominal comparison, i.e. 3D printed object / CAD design of the object; [c] dissolution studies by means of ex-situ time-resolved μCT imaging (often referred to as 4D-CT)1-3.

Our studies demonstrate that μCT can provide vital structural and functional insights of 3D printed pharmaceutical dosage forms and should be considered an indispensable tool in the pharmaceutical technology characterisation toolbox.

^{[1] C. Gioumouxouzis, et al., JDrugDelivSciTec., 40 (2017): 164-171 ;
[2] C. Gioumouxouzis, et al., EurJPharmSci., 120 (2018): 40-52; [3] C. Gioumouxouzis, et al., AAPS PharmSciTech (2018): 1-14}