Polylactic acid/calcium citrate composite: Preparation, characterization and application for delivery of calcium ions

Abstract This work aims to fabricate a biocompatible film for the slow‐release of minerals (calcium) in biomedical applications. Polylactic acid (PLA) was combined with calcium citrate (CC) at different weight ratios of PLA:CC, such as 10:0, 9:1, 8:2, 7:3, 6:4, and 5:5. Their chemical composition, thermal properties and morphology were evaluated and analyzed by FTIR, DSC, TGA and SEM. The results showed that PLA polymer matrices contained a porous structure, and CC was dispersed in their pores. Thermal analysis revealed increased thermal stability and crystallinity of composite PLA/CC with increasing CC content, suggesting interactions. The release of CC from composite film in neutral media followed two stages: (i) a rapid release stage in the first 2.5–3 h, followed by a stable release stage. The weight loss of PLA occurred rapidly in the first two days and then turned to a stable stage from 2 days onwards. The PC5 with a ratio of PLA/CC of 50:50 samples exhibited the highest initial release in comparison with others. The release mechanism of calcium ions from PLA/CC composite followed the Korsmeyer–Peppas kinetic model. These are the preliminary findings for further studies on the release rate of CC and the effect of CC on the role of PLA in different therapeutic applications.