A semi-quantitative spectrophotometric assay for amphotericin B in blood

Rapid Determination of Amphotericin B in Serum and Urine by Third-Order Derivative Spectrophotometry

“…12 A variety of microbiological methods have been described, [13][14][15][16] but they are not adequately sensitive and precise, require long incubations, are difficult to standardize, and pose problems in interpretation especially at low drug concentrations where the natural antifungal activity of blood may interfere with the assay. 15,16 A direct spectrophotometric method for measuring amphotericin B in whole blood and plasma has been also developed, 17 but it seriously suffers from high background absorbance mainly caused by hemoglobin. Several alternative, more specific, high-performance liquid chromatographic methods are also available, [18][19][20][21][22] but their applicability is often limited by interfering endogenous compounds, 22 low extraction efficiency, 18,19 and inadequate reproducibility necessitating use of internal standards.…”