Analysis of 4′‐demethylepipodophyllotoxin‐9‐(4,6‐o‐ethylidene‐β‐d‐glucopyranoside) by high‐pressure liquid chromatography

A rapid and specific high-pressure liquid chromatographic assay is described for the quantitative analysis of 4′-demethylepipodophyllotoxin-9-(4,6-O-ethylidene-β-D-glucopyranoside) (I) in plasma. After chloroform extraction, I was analyzed by reversed-phase chromatography and UV detection (252 nm). The maximum sensitivity was 0.1 μg/ml. Quantitation was by relative response factor calibration using an integrating microcomputer. Over the concentration range of 0.5–90 μg/ml, the average recovery of I from plasma was 95.4 ± 3.8% (SD).