Simultaneous determination of itraconazole, hydroxy-itraconazole and amphotericin B in human plasma by HPLC with photodiode array detection.

A method for the fast analysis of itraconazole, hydroxy-itraconazole and amphotericin B is described which has the advantage of speed and specificity. The method is based on methanolic extraction of the compounds from plasma, followed by reverse-phase high-performance liquid chromatography with two detection wavelengths (263 and 405 nm). The extraction step provides > or = 94% recovery and the response of the detection system is linear from 50 to 5000 ng/ml. No other drugs have been found to interfere with the assay.