INTESTINAL ABSORPTION OF HEPARIN - A STUDY OF INTERACTIONS OF COMPONENTS OF OIL-IN-WATER EMULSIONS

It was previously reported that intraduodenal administration of heparin in an emulsified form to rats and gerbils results in the intestinal absorption of heparin and appearance of serum clearing factor (lipase) activity. The present studies were undertaken to define the effects of the emulsion components on the absorption of heparin as measured by clearing factor activity and to determine optimum composition of the emulsion. Using a threecomponent composite design, the effects of varying heparin, surfactant (an anionic phosphate ester), and oil (trioctanoin) concentrations have been studied simultaneously and the characteristics of the interrelationships analyzed. Clearing factor activity was directly related to the concentration of each of the emulsion components. An inverse relationship was evident for heparin and oil such that the loss of activity resulting from a lowered heparin concentration can, within limits, be compensated for by an increase in the oil concentration. The data suggest that heparin absorption is directly related to and may vary with the particle size and total surface area of the oil droplets. The relationships presented may be unique for the particular surfactant and oil chosen. Copyright © 1969 Wiley‐Liss, Inc., A Wiley Company