Powder bed fusion -laser beam (PBF-LB) three-dimensional (3D) printing: Influence of laser hatching distance on the properties of zolpidem tartrate tablets

Laser sintering, known as powder bed fusion - laser beam (PBF-LB), offers promising potential for the fabrication of patient -specific drugs. The aim of this study was to provide an insight into the PBF-LB process with regard to the process parameters, in particular the laser hatching distance, and its influence on the properties of zolpidem tartrate (ZT) tablets. PHARMACOAT (R) 603 was used as the polymer, while Candurin (R) Gold Sheen and AEROSIL (R) 200 were added to facilitate 3D printing. The particle size distribution of the powder blend showed that the layer height should be set to 100 mu m, while the laser hatching distance was varied in five different steps (50, 100, 150, 200 and 250 mu m), keeping the temperature and laser scanning speed constant. Increasing the laser hatching distance and decreasing the laser energy input led to a decrease in the colour intensity, mass, density and hardness of the ZT tablets, while the disintegration and dissolution rate were faster due to the more fragile bonds between the particles. The laser hatching distance also influenced the ZT dosage, indicating the importance of this process parameter in the production of presonalized drugs. The absence of drug -polymer interactions and the amorphization of the ZT were confirmed.