The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 20, 1976
Filed:
Dec. 20, 1973
John Vnek, New York, NY (US);
Alfred M Prince, Stanford, CT (US);
The Community Blood Council of Greater New York, Inc., New York, NY (US);
Abstract
Highly purified type B hepatitis antigen (HB Ag) is produced from fluid blood material containing such antigen by subjecting blood material containing naturally occurring HB Ag to a double precipitation with polyethylene glycol. In each precipitation, the pH of the fluid blood material is maintained at approximately 4.4 to 4.7 and a polyethylene glycol concentration of approximately 4.0 to 4.5 weight per cent is used. Particularly good results are obtained if the temperature of the material is maintained in the range of 0.degree. to 8.degree.C after the polyethylene glycol has been added. The antigen thus obtained may be further purified by absorption of impurities to hydroxy apatite, followed by isopycnic banding and zonal ultracentrifugation. Hydroxy apatite column chromatography is used to separate the purified antigen into three separate populations of particles.