Monitoring of fluconazole in serum of patients undergoing hemodiafiltration by solid-phase extraction and high-performance liquid chromatography with ultraviolet detection

A high-performance liquid chromatographic assay for monitoring the antifungal drug fluconazole in human serum was developed using a C18 reversed-phase column with isocratic elution. The method involved sample clean-up by solid-phase column extraction, and subsequent analysis required only 14 min per sample for separation and quantitation. The assay was precise, with intra- and inter-assay relative standard deviations of <= 1.5% and <= 3.1%. The minimum detectable concentration of fluconazole was 0.3 nmol/ml. This assay has the advantage of minimizing the risk of interference from co-administered drugs to critically ill patients undergoing hemodiafiltration.