Systematic screening of photopolymer resins for stereolithography (SLA) 3D printing of solid oral dosage forms: Investigation of formulation factors on printability outcomes.

[Display omitted] • Reducing the amount of TPO as low as 0.05% w/w leads to better printability outcomes with the further advantage of reduced costs and lower dose-related toxicity concerns. • The inclusion of high amounts of liquid fillers in photopolymer formulations for SLA 3D printing of medicines should take into account a likely decrease in printing quality of the final dosage form. • Glycerol cannot be used as a liquid filler for PEGDA-based photopolymer resins for SLA 3D printing due to its immiscibility with the photopolymer. Pharmaceutical three-dimensional printing (3DP) is now in its golden age. Recent years have seen a dramatic increase in the research in 3D printed pharmaceuticals due to their potential to deliver highly personalised medicines, thus revolutionising the way medicines are designed, manufactured, and dispensed. A particularly attractive 3DP technology used to manufacture medicines is stereolithography (SLA), which features key advantages in terms of printing resolution and compatibility with thermolabile drugs. Nevertheless, the enthusiasm for pharmaceutical SLA has not been followed by the introduction of novel excipients specifically designed for the fabrication of medicines; hence, the choice of biocompatible polymers and photoinitiators available is limited. This work provides an insight on how to maximise the usefulness of the limited materials available by evaluating how different formulation factors affect printability outcomes of SLA 3D printed medicines. 156 photopolymer formulations were systematically screened to evaluate the influence of factors including photoinitiator amount, photopolymer molecular size, and type and amount of liquid filler on the printability outcomes. Collectively, these factors were found highly influential in modulating the print quality of the final dosage forms. Findings provide enhanced understanding of formulation parameters informing the future of SLA 3D printed medicines and the personalised medicines revolution. [ABSTRACT FROM AUTHOR]