Therapy timeline of numerous diseases and physiological characteristics differ among individuals. The future goal is to consider specifics of each patient and to modify the medicine doses with the use of individual adjusted pharmaceutical products. One of such approaches is also the introduction of two-dimensional printing technology by ex tempore preparation, which can provide real-time dose adjustment of the low-dose APIs. In our work we produced particles consisting of a drug simvastatin and polymer polycaprolactone and monitored reaching the particles of smallest possible size. Particles were prepared by spray drying an emulsion with chloroform as an organic phase and lactose as an antiadhesive material. A spray-drying process parameters giving the smallest particles were determined by using design of experiment. Later, the particles were dispersed in a liquid mixture of propylene glycol and water. The existence of any other process parameters combination, that could result even in smaller particles, was researched using artificial neural network. Our aim was also minimizing adhesion between particles, so other substances like calcium silicate and combination of nanocellulose and lactose were tested in order to examine their influence on size of produced particles. Using scanning electron microscope we found important differences in particle morphology. Smaller particles produced in the presence of lactose and combination of it with nanocellulose were joined into the bigger clusters, while adding calcium silicate in spraying emulsion contributed to individual particles appearing. Despite of similar particle size ranges of each group, we found an important differences also after their dispergation in the medium. Particle clusters of lactose decreased in size due to dissolution of lactose, when the particle clusters produced with combination of nanocellulose and lactose fell apart to individual particles what probably appeared due to the separation of antiadhesive substance from the polymer particle with simvastatin. After dispergation of calcium silicate particles they showed no significant differences in particle size. Parallelly, we evaluated also the influence of different dispergation ways, different liquid mixture viscosity and sample storage for 1 month at room conditions with low humidity to dispersed particle size differences. The appropriate combination of process parameters to reach smallest particle size was established by design of experiment. Potential suitable particles for usage in printing cartridges includes combination of nanocellulose and lactose and are dispersed in liquid mixture containing 90 vol. % of propylene glycol.
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