Abstract: A novel polyaminic resin obtained by crosslinking a polyalkyleneamine (in particular polyethyleneamine) with diisocyanates in solution, is useful as a selective separation or extraction agent of a component having a "complementary" chemical structure (particularly heparin), by means of mere contact or "ionic exchange" with aqueous solutions containing it. Heparin is thus even quantitatively extracted from solutions containing it alone or in mixture with other glucosaminoglycanes. The polyamine can then release the "adsorbed" heparin and be recovered by a treatment with saline solutions. The novel resin is used in pharmaco-biological fields.

Abstract: The use of crosslinked polysaccharides as vehicles for spermicidal substances in compositions used for local contraception is described. The crosslinked polysaccharide (e.g. a modified dextran) is admixed with the spermicidal agent and formed into tablets for vaginal applications; the dextran swells in contact with the vaginal secretion and includes the seminal liquid thus bringing into contact the sperm cells with the spermicidal substances dispersed therein.