ml of cold water for injection the ph of the suspension is adjusted to 5 5 by the addition of 5 acetic acid after mixing the suspension for two hours at 5 u00b0 c 33 3 g of deae sephadex u00ae a 50 pharmacia preequilibrated with 0 3 sodium chloride at ph 5 5 is added after absorption for two hours the deae resin is removed by filtration tri n butyl phosphate tnbp and polysorbate 80 mixture is added to the filtrate to yield a final concentration of 0 3 tnbp and 1 0 polysorbate 80 the solution is incubated overnight at 5 u00b0 c d sorbitol is then added to the treated solution to a final concentration of 33 and the stabilized igg solution is mixed for one 1 hour ph adjusted to 5 5 and heated overnight at 60 u00b0 c the mixture is cooled to 5 u00b0 c and ph is adjusted to 5 8 to remove the solvent detergent peg and sorbitol the mixture is treated with cm sephadex c 50 as follows the solvent detergent treated and heat treated solution is diluted fourfold with cold water the diluted solution is split into three aliquotes sodium chloride is added to the aliquotes to yield a final concentration of 0 2 0 4 and 0 6 for suspensions a b and c respectively each aliquot is then treated with 0 65 g dry weight per gram of protein of cm sephadex u00ae c 50 pharmacia resin pre equilibrated at ph 5 8 and corresponding nacl concentrations after the adsorption of the protein by the resin for 3 u00b1 2 hours the liquid is removed by filtration the protein adsorbed resins are then washed.