Thanks for your post as one of the reason for me to post is to get some cross checking of my assumptions from my all too brief look at EX1.
Yes the two papers I referenced are on immuno affinity capture, but if you look at the claims in the patent application they are very broad (see below) to the point where I think the examiner will throw them out on the basis of the prior art. It looks to me that they are trying to claim anion-exchange purification for exosomes which it a pretty obvious thing for someone to try especially as a first cut. I would be surprised if someone hasn't done this already in the literature.
This does not mean that EX1 doesn't have something of value especially if their method is much faster (it will be cheap), just that they will struggle preventing someone working around the patent. One obvious idea I might try if tasked with working around the patent would be dye-affinity chromotagraphy.
The claims defining the invention are as follows:
1 . A method for obtaining a composition or an isolate of exosomes or microvesicles including:
- providing a liquid that includes exosomes or microvesicles;
- providing a substrate having a surface, the surface having an array of exosome -binding ligands;
- wherein each ligand is in the form of an anionic group or electron rich group; and
- wherein the array of exosome-binding ligands enables exosomes or microvesicles to bind to the substrate;
- contacting the liquid with the substrate in conditions enabling the binding of exosomes or microvesicles to the exosome-binding ligands;
- separating the substrate from the liquid;
thereby obtaining a composition or isolate of exosomes or microvesicles.
2. The method of claim 1 wherein the array is formed from one or more polymers having the exosome-binding ligands.
3. The method of claim 2 wherein the one or more polymers include a monomer species having at least one exosome-binding ligand.
4. The method of claim 3 wherein at least 25% of the monomers of the one or more polymers includes an exosome-binding ligand.
5. The method of any one of the preceding claims wherein all monomers of the one or more polymers have an exosome-binding ligand.
6. The method of any one of the preceding claims wherein each ligand of the array is spaced no more than about 10 angstrom apart from another ligand of the array.
7. The method of anyone of the preceding claims wherein the ligands of the array are spaced apart by more than about 2 angstroms.
8. The method of claim 7 wherein two or more monomeric species include an exosome-binding ligand.
9. The method of any one of the preceding claims wherein part of the substrate surface includes the array.
10. The method of claim 2 wherein the polymer is a polysaccharide or peptide.
1 1 .The method of claim 2 wherein the polymer is a synthetic polymer.
12. The method of claim 2 wherein the one or more polymers form the substrate.
13. The method of claim 2 wherein the one or more polymers are coupled to the substrate.
14. The method of claim 2 wherein the one or more polymers are soluble in the liquid.
15. The method of any one of the preceding claims including the further step of eluting exosomes or microvesicles from the exosome-binding ligands to release the exosomes or microvesicles from the substrate after the substrate is separated from the liquid.
16. The method of claim 1 including the further step of separating the released exosomes or microvesicles from the substrate.
17. An apparatus or device including a substrate according to any one of the preceding claims and enabling the execution of a method according to any one of the preceding claims.
