Table 1: Exposure of microcapsules to the simulated human GI transit (72 h in total) and the corresponding morphological changes.

CompartmentStomachSmall intestineAscend. ColonTransverse colonDescend. Colon
in GI model(V1 )(V2 )(V3 ) (V4 )(V5 )

pH 27.2–7.45.6–5.86.2–6.46.6–6.8
Exposure time (h)24182424
Microcapsule morphology IntactSwelled, ~15% deformedCollapsedCollapsed or dissolvedAdhesive, ~30% ruptured
Microcapsule morphology IntactSlightly swelled, 1% burstSpherical, 2% brokenSpherical intactSpherical intact

Vessel (V) of bioreactors in the GI model representing the human GI tract.
Microcapsules cross-linked by genipin at .
Microcapsules cross-linked by genipin at RT.