PREPARATION OF DISPERSION OF PULMONARY SURFACE ACTIVE SUBSTANCE

PURPOSE:To prepare the titled dispersion without deteriorating the surface activity, by agitating a dispersion obtained by dispersing a pulmonary surface active substance in water or an electrolytic solution under warming. CONSTITUTION:A pulmonary surface active substance is dispersed in water or an electrolytic solution containing sodium ion, potassium ion or magnesium ion, preferably in 0.05-10wt% dispersion concentration. The resultant dispersion is then agitated under warming, preferably at 30-100 deg.C warming temperature, to give the aimed dispersion. The pulmonary surface active substance contains dipalmitoyllecithin which is a phospholipid as a main constituent and is said to have a specific surface activity of changing the surface tension on the inner surface of air cells at expiration and inspiration and exhibit the anti-atelectatic action. The surface activity can be improved easily by the above-mentioned warming treatment.