ABSTRACT
Dissolution testing began at a timewhen pharmaceuticals were both
soluble and permeable. The initial requirement for these immediate
release formulations was testing typically in media consisting of
0.1 N HCl, 50 mM acetate buffers at pH 4.5, or 50 mM phosphate
buffers at pH 6.8 alone or in various combinations. The development
and use of these media conditions is well documented.1,2
Today, oral dosage forms in development have varying levels of
solubility in aqueous media. In order to facilitate the dissolution
testing of drugs that have lower aqueous solubility, surfactants at
low concentrations are allowed by regulatory agencies to enhance
solubility.3 Organic solvents, though sometimes used, are not re-
commended as dissolution media with enhanced solubility since
they typically are not representative of conditions in the gastroin-
testinal tract (GIT). However, bile acids and natural surfactants do
exist in the GIT.
