Determination of 1-aminopropan-2-one, a dissolved sewage component, in water samples

A new method for the determination of 1-aminopropan-2-one (APR) in water samples was developed. APR was synthesised as its hydrochloride and derivatized with 2,4-dinitrophenylhydrazine (DNPH) for determination by high-pressure liquid chromatography with ultraviolet detection (UV-HPLC). APR was determined in water samples at pH 12 using a gas-stripping chamber, connected to a cartridge containing DNPH. Acidified water samples were injected into the gas-stripping chamber and a solution of NaOH added to bring the solution to pH 12. APR was volatilised and stripped from solution and passed onto the cartridge under a constant stream of nitrogen gas. Gas flow rates were carefully controlled to allow maximum contact of APR with DNPH on the cartridge. When the reaction time had elapsed, the cartridge was disconnected and the derivative eluted with a fixed volume of acetonitrile and injected onto the HPLC, where the APR hydrazone was resolved isocratically with a mobile phase consisting of acetonitrile and water (60 : 40). The HPLC was calibrated using standard solutions of the APR hydrazone. Recoveries of APR from standard samples were 90–100% at the 10 μM level and the detection limit for the method was calculated as 18 nM. Detection of APR in urine and primary-treated sewage samples (41 nM and 1.225 μM, respectively) confirmed the applicability of the technique to analysis of environmental samples.