The Sovicell TRANSIL Intestinal Absorption kit measures the affinity of drugs to phosphatidylcholine membranes. It is not only a screening tool to predict intestinal permeability coefficients, but also to predict compounds’ tissue binding. As drug-membrane interactions are key to both the process of membrane permeability and to binding to and permeating into the cell membranes of tissues the assay kit is an ideal tool to predict intestinal permeability rates as well as the volume of distribution early in drug discovery phase. Internal quality controls provide easy assessment of recovery, experiment and data quality.