PHYSIOLOGIC SURFACE-ACTIVE AGENTS AND DRUG ABSORPTION .4. EFFECT OF PRE-MICELLAR CONCENTRATIONS OF SURFACTANT ON DISSOLUTION RATE

The influence of a nonionic surfactant and certain physiologic surfactants and components of gastric juice on the dissolution rate of drug powders was examined. In addition, the effects of pre‐micellar concentrations of surfactant on the dissolution rate of aspirin from commercial dosage forms were determined. Low concentrations of polyoxyethylene (23) lauryl ether (POE lauryl ether), and lysolecithin markedly enhanced the dissolution rate of salicylic acid powder while pepsin and gastric mucin were without effect. Sodium glycocholate was found to increase considerably the dissolution rate of salicylamide powder in pH 6.0 buffer. Both POE lauryl ether and lysolecithin enhanced the dissolution rate of aspirin from a tablet dosage form but were without effect on the dissolution rate of the drug from a capsule dosage form. Good correlation was observed between the surface tensions of the POE lauryl ether solutions and the dissolution rates of aspirin from the tablet dosage form in these media. The relevance of these data to the design of in vitro dissolution tests is discussed. Copyright © 1969 Wiley‐Liss, Inc., A Wiley Company