Innovative 3D Printing Processes for the Production of High-efficiency Drug Release Tablets with Different Drug Loadings

The advent of 3D printing technology has revolutionized the pharmaceutical industry, particularly in the development of personalized medicines. This study explores the fabrication of drug-loaded tablets using the fused deposition modeling (FDM) method, employing polyvinyl alcohol (PVA) as the main polymer matrix and fluorescein as the model drug. The aim of this work is to compare the release profiles of fluorescein in a tablet that is first printed and then impregnated with the tracer, versus a tablet printed using a filament pre-impregnated with the tracer. The PVA filament and tablets were impregnated with a 2% w/v ethanolic solution of fluorescein, followed by a drying process until a constant weight was achieved. Subsequently, the filament underwent the printing process. The printing parameters were established based on literature to ensure good physical-mechanical properties and an optimal drug release profile. Specifically, the parameters considered included printing speed, infill percentage, and layer thickness. Drug release profiles were monitored through dissolution studies under physiological conditions. Fluorescein release was determined using fluorescence spectrophotometry. The results highlighted a significant correlation between the impregnation technique and the release curves, emphasizing how the transport phenomena involved in drug loading affect the release itself; in particular, the impregnation of a tablet showed a penetration of the drug especially in the most external areas of it, determining the release of 65% of the drug after two hours, while the tablet printed with a loaded filament showed a more gradual release of the drug during the dissolution test. This approach demonstrates the potential of 3D printing in the design of efficient and patient-specific drug delivery systems. The study underscores the importance of combining shape studies and printing conditions as formulation strategies in the development of 3D-printed pharmaceutical products, promoting new opportunities for advanced and personalized therapeutic applications.