Ligand-functionalized substrates with enhanced binding capacity

1. An article for biomaterial capture comprising

(a) a porous substrate; and

(b) grafted on said porous substrate, a polymer comprising interpolymerized units of at least one monomer consisting of (1) at least one monovalent ethylenically unsaturated group, (2) at least one monovalent ligand functional group selected from acidic groups, basic groups other than guanidino, and salts thereof, and (3) a multivalent spacer group that is directly bonded to said monovalent groups so as to link at least one said ethylenically unsaturated group and at least one said ligand functional group by a chain of at least six catenated atoms

(c) wherein said monomer is of the formula:

CH 2 ═CR 1 —C(═O)—X—R 2 —[Z—R 2 ] n -L

wherein

R 1 is selected from hydrogen, alkyl, cycloalkyl, aryl, and combinations thereof;

each R 2 is independently selected from hydrocarbylene, heterohydrocarbylene, and combinations thereof;

X is —O— or —NR 3 —, where R 3 is selected from hydrogen, hydrocarbyl, heterohydrocarbyl, and combinations thereof;

Z is heterohydrocarbylene comprising at least one hydrogen bond donor, at least one hydrogen bond acceptor, or a combination thereof;

n is 1; and

L is a heteroatom-containing group comprising at least one monovalent ligand functional group selected from acidic groups, basic groups other than guanidino, and salts thereof.

2. The article of claim 1 , wherein said porous substrate is a porous membrane; and/or wherein said porous substrate is polymeric.

3. The article of claim 1 wherein said monovalent ethylenically unsaturated group is selected from ethenyl, 1-alkylethenyl, and combinations thereof.

4. The article of claim 1 or any other of the preceding claims, wherein said monovalent ligand functional group is selected from carboxy, phosphono, phosphato, sulfono, sulfato, boronato, tertiary amino, quaternary amino, and combinations thereof.

5. The article of claim 1 or any other of the preceding claims, wherein said multivalent spacer group is a catenated heteroatom-containing hydrocarbon group.

6. The article of claim 5 , wherein said hydrogen bonding moiety is selected from carbonylimino, thiocarbonylimino, iminocarbonylimino, iminothiocarbonylimino, oxycarbonylimino, oxythiocarbonylimino, and combinations thereof.

7. The article of claim 1 wherein said chain has at least seven catenated atoms.

8. The article of claim 1 wherein said chain has no more than 50 catenated atoms.

9. The article of claim 1 wherein said chain has from 8 to 16 catenated atoms.

10. The article of claim 1 wherein said polymer is grafted to said porous substrate.

11. A process for preparing an article for biomaterial capture comprising

(a) providing a porous substrate; and

(b) grafting said porous substrate with a polymer comprising interpolymerized units of at least one monomer of the formula:

CH 2 ═CR 1 —C(═O)—X—R 2 —[Z—R 2 ] n -L

wherein

R 1 is selected from hydrogen, alkyl, cycloalkyl, aryl, and combinations thereof;

each R 2 is independently selected from hydrocarbylene, heterohydrocarbylene, and combinations thereof;

X is —O— or —NR 3 —, where R 3 is selected from hydrogen, hydrocarbyl, heterohydrocarbyl, and combinations thereof;

Z is heterohydrocarbylene comprising at least one hydrogen bond donor, at least one hydrogen bond acceptor, or a combination thereof;

n is 1; and

L is a heteroatom-containing group comprising at least one monovalent ligand functional group selected from acidic groups, basic groups other than guanidino, and salts thereof.