Objective: To develop stability-indicating assays for miconazole.
Methods: A reversed phase high-performance liquid chromatographic assay and a bioassay were developed.
Results: The HPLC and the bioassay were linear in the range of 0.5-100 and 0.64-1.56 microg/ml, respectively. The sensitivity of HPLC and bioassay were 0.5 and 0. 64 microg/ml, respectively. The bioassay was less cumbersome and much faster than the HPLC assay by obviating the need for extraction from serum. Miconazole content in the phase-solubility studies and in the serum samples was comparatively evaluated by both assay methods. There was good correlation between the two methods (r2 > 0. 99). The drug extraction efficiency from the serum and the skin were 97.7 and 90.2%, respectively. Where necessary, the bioassay can be an alternative choice for the HPLC analysis. The within and between day variations of the HPLC assay were 3.6 and 4.9%, respectively.