THE WETTING OF POWDERS BY BILE-SALT SOLUTIONS AND GASTRIC-JUICE

Contact angle studies using bile salt solutions and gastric juice have been carried out on phenobarbitone, a model hydrophobic powder. Inter pretation of the results according to the method of Lucassen-Reynders (J. Phys. Chem., 67 (1963) 969-972) shows that the predominant interfa cial adsorption of the surface active components changes with concentr ation. The physical properties of the gastric juice samples were essen tially similar except for surface tension. For a given surface tension , gastric juice wets the hydrophobic powder better than the bile salts .