Cinnamaldehyde loaded-microparticles obtained by complex coacervation: Influence of the process parameters on the morphology and the release of the core material

Encapsulation by complex coacervation includes several steps that have been developed in order to attain a better control over the whole process and to achieve an important delayed effect. This has been carried out for the encapsulation of cinnamaldehyde (CN) by the classical gelatin/acacia gum pair of coacervating polymers. This preparation was performed in different conditions (stirring speeds, cooling rate, emulsion and coacervate time, use of surfactant, and polymer concentration) in order to investigate their effect on the encapsulation efficiency and drug release kinetics. Optical microscopy studies showed spherical microcapsules. The yield of the encapsulation attains more than 88% of all prepared microcapsules. The mean Sauter diameter (d 32) of obtained microparticles was in the range from 124 to 200 µm. The microspheres were also characterized by the FTIR method; showing the presence of core and polymers in the microparticles. The release of cinnamaldehyde was performed in heterogeneous medium (Water / ethanol, v/v: 30/70) at 25±0.5°C using UV–Vis analysis. It was demonstrated that the drug release followed the Fickian diffusion mechanism. The data were best fitted to the Fick's law with high correlation coefficients (R²).