The use of  3D-printed polymers for the generation of prostheses or endoprostheses for biomedical use has grown in recent years. For the correct implantation of the biomedical device in the organism, drugs are impregnated in the polymer, thus providing pharmacoactive properties. The conventional impregnation techniques used to that scope are diverse, being supercritical impregnation one of the most innovative.

The present patent proposal is aimed to use the supercritical impregnation technique to impregnate PLA filaments with natural extracts, one of the polymers that is undergoing the greatest development in this field, prior to the 3D-printing process. In this way, bioactive properties as antioxidant and anti-inflammatory capacity are determined before and after the 3D printing process in order to assess the maintenance of the pharmacological properties of interest. The supercritical impregnation process can degrade the PLA structure so that it cannot be used in the 3D printer. Therefore, the process is aimed at minimizing the damage of the polymer so that it can be used in the printer, as well as ensuring the correct distribution of the extract throughout its structure.