3D printing of starch for the development of personalized drugs

Traditional methods produce medicines with certain parameters, but in many cases without meeting the individual needs of patients. In fact, conventional medications are often based on adult dosing, so pediatric and elderly patients require age-appropriate doses. In addition, certain patient groups also require specific dosage form alternatives to facilitate oral administration of drugs. In this sense, fast-disintegrating tablets stand out as a good option since they dissolve immediately when placed on the tongue. Another challenge that pharmaceutical companies must overcome is the controlled release of the drug over time; especially when the drug has a hydrophobic character, that is, when it is difficult for it to dissolve in water.

In this context, “3D printing technology is an advanced technique for personalized medicine and the development of drug-release tablets on demand,” says Kizkitza González from the ‘Materials+Technologies’ (GMT) group at the University of the Basque Country (UPV/EHU). “The main objective of this work was to produce starch-based 3D printed tablets for the tailor-made administration of hydrophobic drugs”, clarifies the author of the research.

3D printing is a technology that consists of printing products layer by layer, in which materials are deposited according to the digital model designed by computer design software. Following a quick and simple methodology and thanks to 3D printing, “we have been able to prepare tablets based on three types of starch —two types of corn starch (normal and waxy) and one type of potato starch— with different geometries and loaded with a non-soluble drug”, indicates Kizkitza González.

3D printing makes it possible to obtain personalized drugs adapted to different patients. (Image: UPV/EHU)

“The material that is produced must be introduced into a syringe before printing. However, beforehand it is essential to ensure that the material is going to be printable and that once printed it will keep its shape. To do this, a detailed rheological analysis must be carried out”, explains the UPV/EHU researcher. The three types of starch have shown appropriate rheological properties, although in the case of potato starch the printing process turned out to be more laborious due to its properties.

Likewise, “we have observed the importance of the botanical origin of starch in practically all properties such as the porous microstructure, the formation of a stable network or the release of the drug. In the case of normal corn starch, the drug release is instantaneous and the drug is completely released within 10 minutes; In the case of waxy corn starch and potato starch, the release occurs more continuously, and it may take up to 6 hours to be completely released. In addition, we have been able to demonstrate the importance of the geometry of the tablet in the release of the drug”, indicates Kizkitza González.

Finally, “tablets combining different types of starch were also printed. In this case, the release is achieved in two stages. For example, in the case of an infection, in a first stage, with normal corn starch, a drug could be immediately released to relieve pain, and in a second stage, with any of the other two types of starch, a drug could be released. antibiotic more continuously”, says the UPV/EHU researcher.

Kizkitza González is aware that this work is only the first stage of a long process, but assures that “the starch-based 3D printed tablets obtained showed promising properties for future personalized drug delivery applications.”

The study is titled “3D printing of customized all-starch tablets with combined release kinetics”. And it has been published in the academic journal International Journal of Pharmaceutics. (Source: UPV/EHU)