Enzymatic reactions using magnetic particles

Claim 1

A method for carrying out an enzymatic reaction which comprises: (a) contacting an enzyme covalently coupled to magnetically-responsive particles with a reaction medium to form a reaction mixture in a reaction vessel to effect an enzymatic reaction; (b) allowing the enzymatic reaction to occur; and (c) removing the enzyme from the reaction mixture by applying a magnetic field, wherein the magnetically-responsive particles of step (a) individually comprise a magnetic metal oxide core generally surrounded by a coat of polymeric silane, a mass of the particles being dispersable in aqueous media to form an aqueous dispersion having (i) a fifty-percent-turbidity-decrease settling time of greater than about 1.5 hours in the absence of a magnetic field, and (ii) a ninty-five-percent-turbidity-decrease separation time of less than about 10 minutes in the presence of a magnetic field, the magnetic field being applied to the aqueous dispersion by bringing a vessel containing a volume of the dispersion into contact with a pole face of a permanent magnet, the permanent magnet having a volume which is less than the volume of the aqueous dispersion in the vessel.

Claim 2

A method for carrying out an enzymatic reaction which comprises: (a) contacting an enzyme covalently coupled to magnetically-responsive particles with a reaction medium to form a reaction mixture in a reaction vessel to effect an enzymatic reaction; (b) allowing the enzymatic reaction to occur; and (c) removing the enzyme from the reaction mixture by applying a magnetic field, wherein the magnetically-responsive particles of step (a) individually comprise a magnetic metal oxide core generally surrounded by a coat of polymeric silane, a mass of the particles being dispersable in aqueous media to form an aqueous dispersion having (i) a fifty-percent-turbidity-decrease settling time of greater than about 1.5 hours in the absence of a magnetic field, and (ii) a ninty-five-percent-turbidity-decrease separation time of less than about 10 minutes in the presence of a magnetic field, the magnetic field being applied to the aqueous dispersion by bringing a vessel containing a volume of the dispersion into contact with a pole face of a permanent magnet, the permanent magnet having a volume which is less than the volume of the aqueous dispersion in the vessel.

Claim 3

A method for carrying out an enzymatic reaction which comprises: (a) contacting an enzyme covalently coupled to magnetically-responsive particles with a reaction medium to form a reaction mixture in a reaction vessel to effect an enzymatic reaction; (b) allowing the enzymatic reaction to occur; and (c) removing the enzyme from the reaction mixture by applying a magnetic field, wherein the magnetically-responsive particles of step (a) individually comprise a superparamagnetic iron oxide core generally surrounded by a coat of polymeric silane, the iron oxide core including a group of crystals of iron oxide, an individual particle having a mean diameter as measured by light scattering between about 0.1μ and about 1.5μ and a surface area as measured by nitrogen gas adsorption of at least about 100 m 2 /gm, a mass of the particles being dispersable in aqueous media to form an aqueous dispersion having (i) a fifty-percent-turbidity-decrease settling time of greater than about 1.5 hours in the absence of a magnetic field, and (ii) a ninety-five-percent-turbidity-decrease separation time of less than about 10 minutes in the presence of a magnetic field, the magnetic field being applied to the aqueous dispersion by bringing a vessel containing a volume of the dispersion into contact with a pole face of a permanent magnet, the permanent magnet having a volume which is less than the volume of the aqueous dispersion in the vessel.

Claim 4

A method for carrying out an enzymatic reaction which comprises: (a) contacting an enzyme covalently coupled to magnetically-responsive particles with a reaction medium to form a reaction mixture in a reaction vessel to effect an enzymatic reaction; (b) allowing the enzymatic reaction to occur; and (c) removing the enzyme from the reaction mixture by applying a magnetic field, wherein the magnetically-responsive particles of step (a) individually comprise a superparamagnetic iron oxide core generally surrounded by a coat of polymeric silane, the iron oxide core including a group of crystals of iron oxide, an individual particle having a mean diameter as measured by light scattering between about 0.1μ and about 1.5μ and a surface area as measured by nitrogen gas adsorption of at least about 100 m 2 /gm, a mass of the particles being dispersable in aqueous media to form an aqueous dispersion having (i) a fifty-percent-turbidity-decrease settling time of greater than about 1.5 hours in the absence of a magnetic field, and (ii) a ninety-five-percent-turbidity-decrease separation time of less than about 10 minutes in the presence of a magnetic field, the magnetic field being applied to the aqueous dispersion by bringing a vessel containing a volume of the dispersion into contact with a pole face of a permanent magnet, the permanent magnet having a volume which is less than the volume of the aqueous dispersion in the vessel.

Claim 5

A method for carrying out an enzymatic reaction which comprises: (a) contacting an enzyme covalently coupled to magnetically-responsive particles with a reaction medium to form a reaction mixture in a reaction vessel to effect an enzymatic reaction; (b) allowing the enzymatic reaction to occur; and (c) removing the enzyme from the reaction mixture by applying a magnetic field, wherein the magnetically-responsive particles of step (a) individually comprise a ferromagnetic metal oxide core generally surrounded by a coat of polymeric silane, the metal oxide core including a group of crystals of metal oxide, an individual particle having a mean diameter as measured by light scattering between about 0.1μ and about 1.5μ and a surface area as measured by nitrogen gas adsorption of at least about 100 m 2 /gm, a mass of the particles being dispersable in aqueous media to form an aqueous dispersion having (i) a fifty-percent-turbidity-decrease settling time of greater than about 1.5 hours in the absence of a magnetic field, and (ii) a ninety-five-percent-turbidity-decrease separation time of less than about 10 minutes in the presence of a magnetic field, the magnetic field being applied to the aqueous dispersion by bringing a vessel containing a volume of the dispersion into contact with a pole face of a permanent magnet, the permanent magnet having a volume which is less than the volume of the aqueous dispersion in the vessel.

Claim 6

A method for carrying out an enzymatic reaction which comprises: (a) contacting an enzyme covalently coupled to magnetically-responsive particles with a reaction medium to form a reaction mixture in a reaction vessel to effect an enzymatic reaction; (b) allowing the enzymatic reaction to occur; and (c) removing the enzyme from the reaction mixture by applying a magnetic field, wherein the magnetically-responsive particles of step (a) individually comprise a ferromagnetic metal oxide core generally surrounded by a coat of polymeric silane, the metal oxide core including a group of crystals of metal oxide, an individual particle having a mean diameter as measured by light scattering between about 0.1μ and about 1.5μ and a surface area as measured by nitrogen gas adsorption of at least about 100 m 2 /gm, a mass of the particles being dispersable in aqueous media to form an aqueous dispersion having (i) a fifty-percent-turbidity-decrease settling time of greater than about 1.5 hours in the absence of a magnetic field, and (ii) a ninety-five-percent-turbidity-decrease separation time of less than about 10 minutes in the presence of a magnetic field, the magnetic field being applied to the aqueous dispersion by bringing a vessel containing a volume of the dispersion into contact with a pole face of a permanent magnet, the permanent magnet having a volume which is less than the volume of the aqueous dispersion in the vessel.