How does the TRANSIL intestinal absorption compare to octanol/water partitioning?
Frequently membrane permeability is approximated by octanol/water partitioning. The drawback of this system is that permeation of small molecules through membranes depends on structural interactions between the test substance and the membrane such as hydrogen bonding Van der Waals interactions. Since octanol is structurally very different from phospholipid bilayers, it cannot model these interactions well. Octanal/water partitioning has been shown to be particularly poor in predicting permeability of ionized compounds. Our membrane beads are just as good at predicting permeability of ionized and non-ionized compounds and compare well to permeation into liposomes, which is regarded as the gold standard in permeability studies. Moreover, with an incubation of only two minutes our technology is more easily scalable to higher throughput than octanol/water or liposome/water partitioning.
