Meaning
A cell-based assay using human epithelial layers measures the transport of chemicals across the intestinal barrier. In a caco-2 transwell permeation study, cells are grown on a porous membrane to form a functional monolayer. This setup allows scientists to observe how molecules move from the apical side to the basolateral side.
The results help predict the bioavailability of substances that leach from food packaging.
Membrane Barrier
The cell layer acts as a selective filter for different molecular weights. Because caco-2 transwell permeation mimics the human gut, the data is more relevant than simple dissolution tests.
Flux Calculation
Measurements taken over time determine the rate at which a substance passes through the cells. Within a caco-2 transwell permeation experiment, the apparent permeability coefficient is the standard unit of measure. This value accounts for the surface area of the membrane and the initial concentration of the migrant.
High coefficients indicate that a chemical is easily absorbed into the bloodstream. Variations in temperature or pH can alter the permeability of specific plasticizers.
Absorption Prediction
Substances with low transport rates are unlikely to reach internal organs in high concentrations. Data from a caco-2 transwell permeation test supports the ranking of additives by their potential health impact. Manufacturers use these insights to choose safer chemicals for sensitive applications.
