Drugs in Water: Analysis at the Part-per-billion Level Using Direct Supercritical Fluid Extraction of Aqueous Samples Coupled On-line With Ultraviolet–Visible Diode-Array Liquid Chromatography–Mass Spectrometry

Abstract

A high pressure ten port switching valve has provided a means of interfacing a direct aqueous SFE vessel to an LC–MS instrument equipped with a UV/VIS diode-array detector. Analyte trapping and analysis were performed using a coupled octadecylsilane (ODS)–amino column system. Using full scan ammonia chemical ionization, the combined SFE–LC–MS instrumentation enabled the analysis of estrone, hexestrol and zeranol in water each at the 200 ppb level.