| abstract |
Hepatitis B surfact antigen particles (I) are prepd. by treating a fluid from a suitable human donor with (NH4)2SO4 to precipitate an antigen fraction, and then subjecting this fraction to an isopycnic banding and to a rate zonal banding. (I) is recovered in the density rang 1.13-1.16 g./ml. Prepn. is a faster and more economical method for concentrating and purifying (I) obtd from plasma, saliva, faecal extract, nasal pharyngeal secretions, bile, spinal fluid, sweat, urine, semen, vagnal secretions or menstrual blood. |