A novel molecularly imprinted polymer-solid phase extraction method coupled with high performance liquid chromatography tandem mass spectrometry for the determination of nitrosamines in water and beverage samples

Nitrosamines (NAs) as a group of emerging nitrogenous disinfection byproducts were present in drinking water at ng/L levels. Accurate measurements of NAs at such a trace level in samples is a challenging task. Solid phase extraction (SPE), which is used in the sample pretreatment, plays a critical role in the analysis of NAs in water. In this study, a highly selective and sensitive method for the determination of five less polar NAs, namely nitrosodiethylamine nitrosopiperidine, nitrosodi-n-propylamine, nitrosodibutylamine and nitrosodiphenylamine, in water and beverage samples was developed. A new molecularly imprinted polymer (MIP) was synthesized and used as sorbents in SPE for the sample preparation. Prepared samples were analyzed using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Satisfactory recoveries were obtained at three different concentrations (5, 20, and 50 ng/L, n = 3) in the range of 93-107% with relative standard deviations of 3.1-9.8%. Limit of detection and limit of quantitation for the five NAs were in the range of 0.2-0.7 ng/L and 0.6-2.1 ng/L, respectively. Method precisions ranged from 4.9% to 10.5%. This novel method of MIP-SPE coupled with HPLC-MS/MS was successfully applied to the determination of these five NAs in different types of water and beverages samples.