Evaluation of in vitro brain penetration: Optimized PAMPA and MDCKII-MDR1 assay comparison

Parallel artificial membrane permeability assay (PAMPA) is arising in ADMET screening as a powerful tool to determine the passive permeability of new potential chemical entities. In an attempt to set up a sensitive high throughput method to assess passive blood-brain barrier (BBB) penetration we focused our attention on the effect of solvent and the influence of phospholipids on the permeability in PAMPA. Moreover, the high throughput nature of the assay was maximized by decreasing the incubation time and performing the assay in a cassette mode. UPLC system coupled with a mass spectrometer enormously reduces the analytical time, contemporaneously increasing the sensitivity of the method. Papp values obtained from PAMPA were compared to permeability values from MDCKII-MDR1 assay. Evaluation of the two in vitro models with in vivo data was performed to test the predicting capacity of the two methods. Their contemporary assessment was shown to be an helpful tool in understanding the prevalent mechanism of penetration through the BBB. © 2007 Elsevier B.V. All rights reserved.