Selective laser sintering for printing bilayer tablets

In this study Selective Laser Sintering (SLS) was used to produce bilayer tablets containing rosuvastatin and acetylsalicylic acid. Initially, monolithic tablets of each drug were manufactured using different laser intensities in order to identify their impact on the tablet's dissolution, friability and hardness. After the optimization, the final bilayer tablet was fabricated using a new method, that allowed the printing using different powder blends. For that, a 3D-printed casing was employed to maintain the compartments of the tablet in the correct position during the printing process. The results demonstrated that the increased laser intensities led to denser inner cores, enhanced hardness, decreased friability, and slower drug release. Moreover, the new method was able to produce bilayer tablets completely aligned, showing a minor impact on dissolution when the two compartments were printed together in a single tablet. The work demonstrated the feasibility of using SLS in the production of multi-material drug delivery systems.