A method of making a functionalized substrate, wherein the method comprises the steps of: 1) providing a porous base substrate having interstitial and outer surfaces; 2) imbibing the porous base substrate with a first solution to form an imbibed porous base substrate, the first solution comprising (a) at least one grafting monomer having an acrylate group and a photoinitiator group and (b) one or more monomers having at least one acrylate group and at least one additional ethylenically unsaturated, free-radically polymerizable group; and optionally (c) one or more additional monomers having at least one ethylenically unsaturated, free-radically polymerizable group and a hydrophilic group; wherein at least one of (b) or (c) monomers are hydrophilic; 3) exposing the imbibed porous base substrate to a controlled amount of electron beam radiation so as to form a first functionalized substrate comprising grafted photoinitiator group attached to the surfaces of the porous base substrate; and 4) exposing the porous base substrate comprising grafted photoinitiator groups to a controlled amount of UV radiation to crosslink the remaining ethylenically unsaturated, free-radically polymerizable groups. or wherein the method comprises the steps of: 1) providing a porous base substrate having interstitial and outer surfaces; 2) imbibing the porous base substrate with a first solution to form an imbibed porous base substrate, the first solution comprising (a) at least one grafting monomer having an acrylate group and a photoinitiator group; 3) exposing the imbibed porous base substrate to a controlled amount of electron beam radiation so as to form a first functionalized substrate comprising grafted photoinitiator group attached to the surfaces of the porous base substrate; 4) imbibing the first functionalized substrate comprising grafted photoinitiator groups with a second imbibing solution comprising (b) one or more monomers having at least one acrylate group and at least one additional ethylenically unsaturated, free-radically polymerizable group; and optionally (c) one or more additional monomers having at least one ethylenically unsaturated, free-radically polymerizable group and a hydrophilic group; wherein at least one of (b) or (c) monomers are hydrophilic; and 5) exposing the imbibed porous base substrate comprising grafted photoinitiator groups to a controlled amount of UV radiation to crosslink the remaining ethylenically unsaturated, free-radically polymerizable groups. 1) providing a porous base substrate having interstitial and outer surfaces; 2) imbibing the porous base substrate with a first solution to form an imbibed porous base substrate, the first solution comprising (a) at least one grafting monomer having an acrylate group and a photoinitiator group and (b) one or more monomers having at least one acrylate group and at least one additional ethylenically unsaturated, free-radically polymerizable group; and optionally (c) one or more additional monomers having at least one ethylenically unsaturated, free-radically polymerizable group and a hydrophilic group; wherein at least one of (b) or (c) monomers are hydrophilic; 3) exposing the imbibed porous base substrate to a controlled amount of electron beam radiation so as to form a first functionalized substrate comprising grafted photoinitiator group attached to the surfaces of the porous base substrate; and 4) exposing the porous base substrate comprising grafted photoinitiator groups to a controlled amount of UV radiation to crosslink the remaining ethylenically unsaturated, free-radically polymerizable groups. 1) providing a porous base substrate having interstitial and outer surfaces; 2) imbibing the porous base substrate with a first solution to form an imbibed porous base substrate, the first solution comprising (a) at least one grafting monomer having an acrylate group and a photoinitiator group; 3) exposing the imbibed porous base substrate to a controlled amount of electron beam radiation so as to form a first functionalized substrate comprising grafted photoinitiator group attached to the surfaces of the porous base substrate; 4) imbibing the first functionalized substrate comprising grafted photoinitiator groups with a second imbibing solution comprising (b) one or more monomers having at least one acrylate group and at least one additional ethylenically unsaturated, free-radically polymerizable group; and optionally (c) one or more additional monomers having at least one ethylenically unsaturated, free-radically polymerizable group and a hydrophilic group; wherein at least one of (b) or (c) monomers are hydrophilic; and 5) exposing the imbibed porous base substrate comprising grafted photoinitiator groups to a controlled amount of UV radiation to crosslink the remaining ethylenically unsaturated, free-radically polymerizable groups.