SUBSTANCE ACTIVATING LUNG SURFACE AND ITS PREPARATION

PURPOSE:A substance activating lung surfaces is dissolved in an organic solvent and brought into contact with an adsorbent to effect selective removal of protein, thus preparing a protein-free substance activating lung surfaces used as a remedy for hyperpnea syndromes without reduction in its surface activity. CONSTITUTION:A substance activating lung surfaces, which is obtained from extract of mammarian lung tissuses or lung-rinsing solution by isolation and purification such as centrifugation, is dissolved in an organic solvent dissolving phospholipid, preferably in a concentration of 0.1-10W/V%. An adsorbent such as activated carbon or silica gel is added to the solution, then the absorbent containing proteins is removed, and the organic solvent is distilled off to give substatntially protein-free substance activating lung surfaces originating from an animal other than human.