Leucocyte depleting filter device and method of use

Claim 2

A leucocyte depletion filter assembly for removing leucocytes and other deleterious mater from a biological fluid in an extracorporeal circuit, the filter assembly comprising: a housing having an inlet and an outlet and defining a liquid flow path between the inlet and the outlet, and a pleated medium positioned inside the housing across the liquid flow path and including a fibrous means for decreasing the leucocyte content of the liquid, the surface of said fibrous means being modified by exposure to a gas plasma stream, wherein said fibrous means is capable of permitting the passage of red blood cells and platelets therethrough.

Claim 3

The leucocyte depletion filter assembly of claim 1 having a capacity of six liters per minute at a differential pressure less than 15 psi.

Claim 4

The leucocyte depletion filter assembly of claim 1 having a hold up volume in the range from about 70 cc to about 400 cc.

Claim 5

The leucocyte depletion filter assembly of claim 1 wherein the fibrous means has a hollow, generally cylindrical configuration.

Claim 6

The leucocyte depletion filter assembly of claim 1 wherein the fibrous means has a CWST of at least 52 dynes/cm.

Claim 7

The leucocyte depletion filter assembly of claim 1, wherein said gas plasma is generated from an inorganic gas.

Claim 8

The leucocyte depletion filter assembly of claim 1, wherein said gas plasma is generated from an organic gas.

Claim 9

The leucocyte depletion filter assembly of claim 1, wherein said gas plasma is generated from a gas selected from the group consisting of helium, argon, nitrogen, neon, nitrous oxide, nitrogen dioxide, oxygen, air, ammonia, carbon monoxide, carbon dioxide, hydrogen, chlorine, hydrogen chloride, bromine cyanide, sulfur dioxide, hydrogen sulfide, xenon, krypton, and mixtures thereof.

Claim 10

The leucocyte depletion filter assembly of claim 8, wherein said gas is oxygen.

Claim 11

The leucocyte depletion filter assembly of claim 1, wherein said pleated medium is of fibers of a synthetic resin.

Claim 12

The leucocyte depletion filter assembly of claim 10, wherein said synthetic resin is a member selected from the group consisting of polyolefin, polyesters, polysulfones, polyaramides, acrylics, polyarylene oxides, polyarylene sulfides, and polymers and copolymers made from halogenated olefins.

Claim 13

The leucocyte depletion filter assembly of claim 11, wherein said synthetic resin is a polyester.

Claim 14

The leucocyte depletion filter assembly of claim 12, wherein said polyester is polybutylene terephthalate.

Claim 15

The leucocyte depletion filter assembly of claim 13, wherein said pleated medium has been treated with an oxygen gas plasma at about 40 kilohertz, about 2 kilowatts, and about 100-150 mtorr for about 10-30 minutes.

Claim 16

The leucocyte depletion filter assembly of claim 1, wherein said plated medium has been treated with a gas plasma at about 10 to about 3000 watts, about 1 kHz to about 100 MHz, and about 0.001 to 100 torr for about 5 seconds to about 12 hours.

Claim 17

The leucocyte depletion filter assembly of claim 15, wherein said pleated medium has been treated with a gas plasma at about 500 to about 2500 watts, about 15 kHz to about 60 MHz, and about 0.01 to 1 torr for about 1 minute to about 2 hours.

Claim 18

The leucocyte depletion filter assembly of claim 16, wherein said pleated medium has been treated with a gas plasma at about 1500 to about 2500 watts, about 30 kHz to about 50 kHz, and about 0.1 to 1 torr for about 10 minutes to about 30 minutes.

Claim 19

The leucocyte depletion filter assembly for removing leucocytes and other deleterious matter from a biological fluid in an extracorporeal circuit, the filter assembly comprising: a housing having an inlet, an outlet, and a vent and defining a liquid flow path between the inlet and the outlet; a degassing mechanism communicating with the vent for removing gas from the biological fluid; and a pleated fibrous medium positioned in the housing across the liquid flow path, the surface of said fibrous medium having been modified by exposure to a gas plasma stream, said fibrous medium being capable of decreasing the leucocyte consent of the biological fluid and permitting the passage of red cells and platelets therethrough.

Claim 20

The leucocyte depletion filter assembly for removing leucocytes and other deleterious matter from a biological fluid in an extracorporeal circuit, the filter assembly comprising: a housing having an inlet, an outlet, and a vent and defining a liquid flow path between the inlet and the outlet; a degassing mechanism communicating with the vent for removing gas from the biological fluid; and a pleated fibrous medium positioned in the housing across the liquid flow path, the surface of said fibrous medium having been modified by exposure to a gas plasma stream, said fibrous medium being capable of decreasing the leucocyte consent of the biological fluid and permitting the passage of red cells and platelets therethrough.

Claim 21

The leucocyte depletion filter assembly of claim 18 having a capacity of six liters per minute at a differential pressure less than 15 psi and having a hold up volume in the range from about 70 cc to about 400 cc.

Claim 22

A leucocyte depletion filter assembly for removing leucocytes and other deleterious matter from a biological fluid in an extracorporeal circuit, the filter assembly comprising: a generally cylindrical housing having first and second chambers, an inlet which allows tangential inflow into the first chamber, an outlet which allows outflow from the second chamber, and a vent; a porous degassing element position end between the first and second chambers to remove gas from the biological fluid; a liquophobic membrane covering the vent and communicating with the degassing element to allow gas but not liquid to flow through event; and a hollow, cylindrical porous medium positioned in the second chamber and comprising a pleated fibrous medium having a CWST of 52 dynes/cm or greater, the surface of said fibrous medium having been modified by exposure to a gas plasma stream, said fibrous medium being capable of decreasing the leucocytes content of the biological fluid and permitting the passage of red cells and platelets therethrough, and the interior of the hollow pours medium communicating with the outlet.

Claim 23

A leucocyte depletion filter assembly for removing leucocytes and other deleterious matter from a biological fluid in an extracorporeal circuit, the filter assembly comprising: a generally cylindrical housing having first and second chambers, an inlet which allows tangential inflow into the first chamber, an outlet which allows outflow from the second chamber, and a vent; a porous degassing element position end between the first and second chambers to remove gas from the biological fluid; a liquophobic membrane covering the vent and communicating with the degassing element to allow gas but not liquid to flow through event; and a hollow, cylindrical porous medium positioned in the second chamber and comprising a pleated fibrous medium having a CWST of 52 dynes/cm or greater, the surface of said fibrous medium having been modified by exposure to a gas plasma stream, said fibrous medium being capable of decreasing the leucocytes content of the biological fluid and permitting the passage of red cells and platelets therethrough, and the interior of the hollow pours medium communicating with the outlet.

Claim 26

The method of claim 21 wherein up to six liters per minute of biological fluid are placed through the fibrous medium.

Claim 27

The method of claim 21, wherein said gas plasma is generated from a gas selected from the group consisting of helium, argon, nitrogen, neon, nitrous oxide, nitrogen dioxide, oxygen, air, ammonia, carbon monoxide, carbon dioxide, hydrogen, chlorine, hydrogen chloride, bromine cyanide, sulfur dioxide, hydrogen sulfide, xenon, krypton, and mixtures thereof.

Claim 28

The method of claim 21, wherein aid pleated medium has been treated with a gas plasma at about 10 to about 3000 watts, about 1 kHz to about 100 MHz, and about 0.001 to 100 torr for about 5 seconds to about 12 hours.

Claim 29

The method of claim 21, wherein the fibrous medium comprises a synthetic resin selected from the group consisting of polyolefins, polyesters, polysulfones, polyaramides, acrylics, polyarylene oxides, polyarylene sulfides, and polymers and copolymers made from halogenated olefins.

Claim 30

The method of claim 25, wherein said polyester is polybutylene terephthalate.

Claim 31

The method of claim 26, wherein said pleated medium has been treated with an oxygen gas plasma at about 40 kilohertz, about 2 kilowatts, and about 100-150 mtorr for about 10-30 minutes.

Claim 34

The method of claim 28 wherein directing the fluid through a housing comprises repeatedly circulating the biological fluid through the housing.

Claim 39

The method of claim 31 wherein directing the fluid through a housing comprises repeatedly circulating the biological fluid through the housing.