Abstract: The invention relates to a method of preparing a reagent for the determination by hemagglutination of antibodies to bacterial toxins. According to this method erythrocytes are treated with glutaraldehyde and then with the bacterial toxins in the presence of glutaraldehyde without a wash step. The reagent thus obtained is further treated with a reagent for blocking aldehyde groups.

Abstract: According to the invention, the antitumor agent such as daunorubicin and a well-defined quantity of a bifunctional crosslinking agent, such as glutaraldehyde, are brought together. A form of polymeric product is obtained, which is insoluble in aqueous media but which, on being resuspended in an aqueous medium in the absence of glutaraldehyde, gradually releases the antitumor agent in a soluble form, preserving its antitumor activity. Improvement of the conditions of treatment with antitumor agents.

Abstract: Improvement in the preparation of allergens, for the obtention of more stable and more effective preparations from extracts of various materials such as pollens, house dust, kapok, wool, molds, etc. extracts containing only allergenic substances having molecular weights in the range of from about 10,000 and 50,000 and being free from enzymes are broadly contemplated.The substances have no allergenic activity are removed from the aqueous extract. In particular, molecular masses below 14,000 and above 45,000 are eliminated.The allergen thus improved is suitable in the adsorbed form, for example, on alumina and phosphates of aluminum or of calcium; it provides particularly good results when the adsorbent is a special phosphate in which the ponderal ratio Ca/P is 1.55 to 1.90.