Whole blood leukodepletion and platelet filter

DETAILED DESCRIPTION Most blood available as a source for cell separation is whole, and not pre-fractionated.
It generally is packaged in one unit (approximately 350-450 ml) plastic bags and is citrated to prevent clotting.
Once blood becomes outdated for use in fresh transfusions, it may be fractionated.
It would be highly desirable to be able to leukodeplete and separate platelets and RBC from such blood stores directly and immediately rather than wait until it is partially fractionated.
Accordingly, it is an object of the present invention to provide blood cell fractionation means for removing leukocytes from whole blood while permitting recovery in high yield of platelets and red blood cells.
It is a further object of the present invention to obtain efficacious cell fractionation through a filter without leaching of coating materials which facilitate the differential separation.
It is a further object to be able to coat filters and other cell fractionation means so that permanency is attained without covalent interaction with the filter matrix itself, requiring particular functional groups which may interfere with or defeat the object of differential cell separation.
Summarizing briefly, the present invention provides blood cell fractionation means comprising a filter matrix, preferably having a fibrous structure, which is coated with a chemical condensation product, prepared by reaction insitu of a first electrophilically active, high molecular weight polyalkylene oxide, and a second high molecular weight polyalkylene oxide derivative, which is either a tetraaminopolyalkylene oxide or a bifunctional dihydroxy-polyaxyalkylene oxide derivative, or combination thereof.
Alternatively, in another embodiment, the coating may be an isopolymer of a high molecular weight tetraacrylatepolyalkylene oxide, polymerized by exposure to radiation.
Alternatively, in another embodiment, the coating may be a chemical condensation product, prepared by reaction insitu of a first electrophilically active, high molecular weight polyalkylene oxide and a bifunctional diamino-polyalkylene oxide derivative