Electrophotographic 3D printing of pharmaceutical films

The usage of three-dimensional (3D) printing in pharmaceutical applications offers significant advantages compared to conventional manufacturing approaches such as tableting or encapsulation. Laser sintering (LS), also referred to as powder bed fusion - laser beam (PBF-LB), formerly also known as selective laser sintering (SLS), offers the production of pharmaceuticals directly from a powder mixture with high geometrical flexibility and adjustable release profiles. However, due to limitations of conventional powder application methods for PBFLB, neither the material composition nor the material distribution can be tailored within a printed layer. To overcome these restrictions, electrophotographic powder application (EPA), a novel method for selective powder application, was utilized in this study. EPA allows the deposited layer thickness to be reduced to values between 12 and 76 & mu;m, depending on the used pharmaceutical powder blend. Thus, the laser energy input required for interlayer connection can be reduced, enabling the use of a CO2 laser. In this study, for the first time, EPA in combination with powder bed fusion - laser beam of polymers (EPA-PBF-LB/P) was utilized to successfully deposit and print three different model drugs: paracetamol, nicotinamide, and caffeine, mixed with Eudragit L 100-55, a pharmaceutical grade polymer. Through the use of EPA, thin layers of powder blends were successfully deposited in the build chamber, leading to no thermal degradation of the polymer or drugs from the use of a CO2 laser. Single- and multi-material pharmaceutical films were successfully printed via EPA-PBF-LB, utilizing EPA to selectively as well as precisely apply different powders within a single layer into the build chamber. This introduces a novel method of printing pharmaceuticals using SLS with a CO2 laser and without the use of additional colorants.