pION INC has been awarded a patent for its Double-Sink™ PAMPA method. The International patent covers most European countries. This compliments our corresponding U.S.A. patent for Double-Sink PAMPA method.

pION was first to commercialize the PAMPA permeability method.

Double-Sink PAMPA is a unique analytical method for measuring permeation across an artificial membrane. It offers a significantly improved dynamic range allowing fundamental permeation properties of drug molecules to be determined quantitatively rather than qualitatively.

A wealth of permeability information can be extracted from well-designed Double-Sink experiments. The method is especially helpful when measuring today’s highly lipophilic ionizable drug prospects in a high-throughput fashion.

A dynamic range expanded 10 to 500 times towards higher values, combined with innovative software for controlling robotic liquid handling platforms and extraction of property data, vastly improves the value of the measured data, which are well correlated with published human intestinal and blood-brain barrier data.

pION’s Double-Sink method accomplishes this by creating a permeation cell with two chambers separated by a filter-supported lipid membrane. The compound to be measured is added to a pH buffer on one side of the membrane while a scavenger agent is added to a buffer on the opposite side. The scavenger ensures sink conditions on the receiving side of the membrane throughout the timed experiment. A flipping stirring bit on the donor side keeps the aqueous boundary layer as thin as possible. It is this boundary layer that limits the maximum measured permeability value. Much used orbital shaking has proven ineffective in 96-well microtiter plates.

Because pH of the individual donor wells can be set robotically, the Double-Sink PAMPA method makes it possible to measure a detailed pH-permeability profile over the range of 3 to 10 pH and from 10 -8 cm/s to 10 -3 cm/s.

pION scientists have published 30 supporting papers on permeability measurements in peer reviewed journals.