Screening for unknown compounds by HPLC using a multichannel diode array UV‐VIS spectrophotometer: Application to drug metabolism

This article describes the use of a multichannel UV‐VIS detector coupled on‐line to an HPLC instrument. Simultaneous measurements of the absorption of a compound over a full range of wavelengths (200–800 nm) makes this almost universal detector a useful tool in screening for unknown compounds. The procedures used to compute so‐called spectro‐chromatograms and to draw pseudo‐three‐dimensional plots are discussed. The experimental examples given include an application to screening for drug metabolites in biological fluids.