Release Studies of Thymol and p-Cymene from Polylactide Microcapsules

The objective of this work is to access the release behavior of thymol and p -cymene used as model core materials with PLA microcapsules. The microcapsules were obtained by a coacervation process developed in a previous work and present a spherical shape with mean particle size of 25 and 37 μm for thymol and p -cymene, respectively. The results have shown that the release of thymol and p -cymene is faster in the first hour keeping almost constant in the subsequent days. The diffusion coefficient in the first hour of release was 1.99 × 10 –16 m 2 /s for thymol and 4.34 × 10 –16 m 2 /s for p -cymene. However, the diffusion was slower if considering a period of 5 days being the diffusion coefficients of 3.34 × 10 –19 m 2 /s for thymol and 3.45 × 10 –18 m 2 /s for cymene.