[A two-step method of purifying the surface antigen of the hepatitis B virus and its use in the passive hemagglutination reaction for indicating antibodies to the surface antigen of the hepatitis B virus].

A simple and economic scheme for the purification of HBsAg has been developed: step I--immunosorption with the use of a cellulose suspension with immobilized purified anti-HBs, and step II--isopycnic ultracentrifugation through CsCl. This method yields a 300-fold purified HBsAg, its harvest being 75%. An erythrocytic immunodiagnosticum for the passive hemagglutination test has been prepared on the basis of this purified HBsAg; the sensitivity of the test with this immunodiagnosticum is but slightly inferior to that of radioimmunoassay.

[Study of lysozyme by a spin-label method in the 2-mm range].

Two millimeter range ESR-spectroscopy was used to measure the values of magnetic resonance parameters of egg lysozyme samples modified with nitroxyl label 4-(iodine-acetamide)-2,2,6,6-tetramethylpiperidine-1-oxyl by hist-15 residue. It has been shown that in a lyophilic sample the spin label forms a hydrogen bond with the protein group and when the sample is moistened--with water molecules. Temperature changes of the pattern of ESR line are analysed.