title: Removal of beta-2-microglobulin by diffusion alone is feasible using highly permeable dialysis membranes.
abstract: Techniques of filtration with high flux dialysis membranes are capable of easily removing beta-2-microglobulin (beta-2-M) (MW: 11,800) from renal failure patients. However, hemodialysis is preferred as a method of removing beta-2-M in terms of cost and operation. The present study elucidates the permeability characteristics for beta-2-M of newly developed cellulosic and synthetic polymer membranes for hemodialysis to determine the diffusive clearance for beta-2-M. The authors did dialysis experiments with 3H-labeled water and 125I-labeled beta-2-M to obtain the solute permeability of cellulosic and synthetic polymer membranes. Radioactivity of a single hollow fiber after dialysis experiments for predetermined periods was measured in a gamma counter. Through analysis of radioactivity data, they obtained solute permeability data, from which diffusive clearance for beta-2-M was calculated. With wet cellulose triacetate membranes, values for inside diameter, wall thickness, and water content were 205 +/- 10 microns (N = 100), 12.4 +/- 1.5 microns (N = 200), and 78 vol%, respectively. The cellulose triacetate membranes had a solute permeability for beta-2-M of (4.12 +/- 1.83) x 10(-5) cm/sec (N = 25) and a pure water permeability of 60 ml/m2/hr/mmHg. Diffusive clearance for beta-2-M was calculated to be 39 ml/min at a plasma flow rate of 160 ml/min and a dialysate flow rate of 500 ml/min. The diffuse clearance of capillary dialyzers composed of regenerated cellulose and synthetic polymer membranes ranged from 23 to 19 ml/min.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Chemical Engineering, Waseda University, Tokyo, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Naitoh
authors.forename: T
authors.initials: T
authors.lastname: Tatsuguchi
authors.forename: M
authors.initials: M
authors.lastname: Okada
authors.forename: T
authors.initials: T
authors.lastname: Ohmura
authors.forename: K
authors.initials: K
authors.lastname: Sakai
mesh_terms: D000180:Acrylic Resins; D002482:Cellulose / Q000031:analogs & derivatives; D004058:Diffusion; D006801:Humans; D008567:Membranes, Artificial; D009211:Myoglobin / Q000032:analysis; D010539:Permeability; D011145:Polyvinyls; D006435:Renal Dialysis / Q000295:instrumentation*; D014462:Ultrafiltration / Q000295:instrumentation; D001613:beta 2-Microglobulin / Q000032:analysis*
chemical_list: D000180:Acrylic Resins; D008567:Membranes, Artificial; D009211:Myoglobin; D011145:Polyvinyls; D001613:beta 2-Microglobulin; C016438:ethylenevinylacetate copolymer; C010504:polyacrylonitrile; D002482:Cellulose; C024671:cellulose triacetate