Biopolymer Hydroxypropyl Methylcellulose-Based Filaments Prepared by Hot-Melt Extrusion Suitable for Fused Deposition Modeling 3D Printing of Personalized Capsules

Materials based on the hydroxypropyl methylcellulose mixed with different biopolymers (BioP; 5 w% of chitosan, sodium alginate, apple pectin, or citrus pectin) were processed by hot-melt extrusion and 3D printing to produce capsules intended for controlled drug release. Microscopic analyses confirmed significant impact of BioP on the processing temperatures and quality of the 3D printing. The capsules' chemical composition had a more significant impact on the dissolution profiles in acidic and neutral media, which are a robust function of the intermolecular bonds and swelling characteristics of the particular BioP (as indicated by the combined results of Raman spectroscopy, differential scanning calorimetry [DSC], and thermogravimetry). The capsules of all tested compositions retained the model drug for 120 min in pH 1.2, i.e., fulfilled the condition of targeting the small intestine. The presence of the particular BioP was found to be particularly beneficial in the development of personalized capsules for oral administration. The addition of both pectins led to a relatively fast pH-independent release of the model drug and has the potential applications in the targeting of the duodenum or jejunum. The capsules containing alginate and chitosan exhibited later initial release in pH 1.2, guaranteeing an unaltered passage through the stomach environment.