The invention discloses a method for separating
human immune globulin from
plasma, which comprises the following steps: S1,
plasma pretreatment: filtering fresh
plasma by using a 0.45 mu m filter membrane, adjusting the pH value to 5.0-5.5, adding PEG6000 (
Polyethylene Glycol 6000) with the final concentration of 2% to precipitate impure
protein, and centrifuging to take supernatant; s2, cation exchange
chromatography: loading the supernatant to a Capto S
Impact chromatographic column, balancing by using a
sodium acetate
buffer solution containing 50-100 mM of NaCl, carrying out
gradient elution by using 0-500 mM of NaCl, and collecting an IgG main peak; s3, hydrophobic
chromatography: adjusting the concentration of
ammonium sulfate in the eluent in S2 to 1.0 M, loading to a Phenyl HP column, carrying out reverse
gradient elution by using 1.0-0 M
ammonium sulfate, and collecting a target peak; s4,
virus inactivation: 0.3% of Tween-80 and 0.25% of TNBP are added, and incubation is performed for 6 hours at the temperature of 25 DEG C; and S5,
ultrafiltration sterilization: concentrating to 100 mg / mL by using a 30 kDa tangential flow
ultrafiltration system, and filtering and sub-packaging at 0.22 mu m. Through the CEX-HIC
coupling technique,
gradient elution optimization and integrated
virus inactivation, efficient, low-cost and safe production of high-purity intravenous injection IgG is achieved, and the method is particularly suitable for large-scale application in the
blood product industry.