Abstract
This study aims to investigate the variation of the 3D printers Ultimaker 3 and ZMorph VX by printing 80 cylindrical products from the same model on different positions on the build plate and comparing the diameter, height and mass. In addition, the temperature variations of the nozzle, build plate and product were evaluated in a separate experiment performed on key positions on the build plate. For the variability studies, a commercially available PLA filament was used as printing material. In order to load drug into the filament, a new method for direct powder extrusion was developed. The Ultimaker was used to print a polypill containing caffeine, paracetamol and indomethacin by direct powder extrusion. Both printers showed low variation in diameter, height and mass of the printed products with RSD < 2 %. With the exception of the diameter of the printed products, the dimensional error compared to the designed model was quite low for both printers, and similar to results found in literature. The results from the temperature study showed lower temperatures in the lower positions on the build plate for the Ultimaker 3 as well as a reduction in temperature of printed products as the printing continued. The ZMorph VX overall showed stable temperatures for the nozzle and build plate. The product temperatures showed larger variation than on the Ultimaker 3, which most likely have been caused by interference of the heated nozzle. The preliminary work that has been done in this thesis suggests that the Ultimaker 3 coupled with a new method of direct powder extrusion is a suitable method for manufacturing a polypill. Dissolution testing of the polypill showed a linear release-profile where approximately 50 % of the drug-loaded indomethacin had dissolved within 2 hours. Due to the recent shutdowns of the University of Oslo in response to Covid-19, the characterization of the polypill was not completed. Hence, further studies should be performed to accurately depict the characteristics of the polypill.