Chromatographic two-layer particles
View Patent ↗The present invention is a method of producing a chromatographic separation matrix, wherein porous polymeric particles comprised of two layers with different properties are prepared in a two-phase system by (a) providing porous polymeric particles with reactive groups on their surfaces; (b) washing said particles with a first solvent and draining the particles to enclose a first phase; (c) wetting the outer layer of the particles by adding a second solvent, which is essentially insoluble in the first solvent; (d) reacting the reactive groups in the outer layer by adding a reagent, which is essentially non-reactive in the first solvent; and (e) coupling of chromatographic binding groups to the reactive groups in the inner layer. The invention also encompasses a porous polymer particle suitable for use as a chromatographic separation matrix and a process of separation, wherein a matrix according to the invention is used.
1. A method of producing a chromatographic separation matrix of porous polymeric particles including two layers with different properties said method comprising:
(a) providing at least one porous polymeric particle that presents reactive groups on its pore surfaces and on its external surface;
(b) washing said particle with a first solvent and draining the solvent to obtain a first phase enclosed in said at least one particle;
(c) wetting an enclosing outer layer of the particle by adding a second solvent, which solvent is essentially insoluble in the first solvent, to provide a second phase on the outer layer;
(d) reacting the reactive groups in the outer layer by adding a reagent, which is essentially non-reactive in the first solvent; and
(e) coupling chromatographic binding groups to the reactive groups in the inner layer.
2. The method of claim 1 , wherein the reactive groups are carbon-carbon double bonds.
3. The method of claim 1 , wherein the particle is made from a polymer comprising pendent hydroxy groups.
4. The method of claim 3 , wherein the particle in step (a) is made by allylation of the pendent hydroxy groups with allyl glycidyl ether (AGE) to provide reactive allyl groups.
5. The method of claim 1 , wherein the reagent added in step (d) is an oxidizing agent that is reactive in aqueous phases.
6. The method of claim 1 , wherein the reagent added in step (d) is an oxidizing agent that is reactive in organic phases.
7. The method of claim 1 , wherein the first solvent enclosed in the particle is an organic solvent.
8. The method of claim 1 , wherein the first solvent enclosed in the particle is an aqueous solution.
9. The method of claim 8 , wherein the aqueous solution includes an emulgator.
10. The method of claim 1 , wherein up to about 30% of the reactive groups as originally present in the particle are reacted in step (d).
11. The method of claim 4 , wherein the coupling according to step (e) is performed by radical activation of the allyl groups to allow coupling of binding groups.
12. The method of claim 1 , wherein the binding groups of step (e) are ion exchange groups.
13. The method of claim 1 , further comprising modifying the groups in the outer layer and coupling the chromatographic binding groups to the surface thereby producing a bifunctional chromatographic separation matrix.