COMPARISON OF HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY AND BIOASSAY OF AMPHOTERICIN-B IN SERUM

For the determination of amphotericin B in serum a high-performance li quid chromatography (HPLC) method using simple protein precipitation a nd an isocratic mobile phase as well as a plate diffusion bioassay are described. Using 5-fluorocytosine-resistant strain of Candida albican s and peptone in medium as an antagonist of 5-fluorocytosine allows si mple measurement of amphotericin B both in the absence and in the pres ence of 5-fluorocytosine. The correlation coefficient (r) between bioa ssay and HPLC runs is 0.88. Generally, the biological determination gi ves slightly higher values of amphotericin B than the HPLC method. Bot h methods are useful for amphotericin B drug monitoring.