MONTREAL—Early last month, ProMetic Lifes Sciences Inc. and Goettingen, Germany-based Sartorius AG entered into a pair of collaborative agreements in the area of protein purification. Under one agreement Sartorius will be a preferred supplier and technology provider for filtration equipment and consumables to ProMetic for its blood plasma fractionation process called the "Plasma Protein Purification System" (PPPS).
In addition, the two companies have agreed to collaborate on the development of ligand-membrane composites which researchers can use for the isolation of proteins from blood plasma and other sources. These affinity composites will be created using ProMetic's Mimetic Ligand technology in conjunction with Sartorius' membrane chromatography technology called Sartobind.
Financial terms of the two agreements were not released.
The new membrane—as yet unnamed—has the potential to plug a gap in the market in applications where conventional chromatography columns aren't effective, according to Steve Burton CEO of ProMetic Biosciences, a division of ProMetic Life Sciences. "Chromatography is effective in situations where you have a relatively high concentration of the target protein, because one of the advantages of chromatography is it has a high intrinsic capacity—a small volume of bead can capture a large amount of protein," Burton says. "But if one tries to push liquid through at too high a flow rate, the beads tend to compact into each other and the flow channels are reduced in size and that places a limitation on the throughput in a chromatography column."
Such a limitation doesn't exist with a membrane method, he notes, because the membrane is non-compressible which allows for much higher flow rates. "For researchers processing relatively high volumes where you have a dilute protein, membranes have a much better capacity to cope with the higher flow rates," says Burton.
With Sartorius providing the membrane technology, ProMetic's contribution to the collaboration will be its expertise in creating synthetic organic entities the company calls "Mimetic Ligands". These ligands are very different from antibodies and peptides but are synthetic entities that mimic and even enhance the natural molecular affinity of binding ligands toward target biomolecules.
"This gives us a lot of flexibility since we are not restricted by what nature can provide," Burton says. "The number of different ligands we can synthesize is truly mind-boggling—probably billions of different structures. So that means we have the ability to pretty much identify a ligand for any protein target."
The result will be a membrane filtering technology that can target virtually any protein.
While neither company has put a time-table on when the first products might hit the market—sometime in early 2007 is the best estimate—the intention is to initially provide off-the-shelf materials that hit a broad swath of the research market. Down the road, there is potential to provide more specialized combination membrane-ligand products for specific applications.