Selective extraction of synthetic cathinones new psychoactive substances from wastewater, urine and cocktail using dummy molecularly imprinted polymers

Dummy molecularly imprinted polymers (DMIPs) for selective extraction of five common synthetic cathinones (SCs) were prepared by bulk polymerization. DMIPs materials possessed narrow diameter distribution (30-60 µm) and large specific surface area (329.6 m2 g-1). Imprinting factors for cathinone, methcathinone, mephedrone, methylone and ethylone were 1.11-1.82. DMIPs could also quickly adsorb SCs from aqueous solutions within 5 min. Therefore, the materials were used as solid-phase extraction (SPE) sorbents to selectively extract five SCs in complex samples. An accurate and sensitive analytical method based on DMIPs-SPE combined with HPLC-MS/MS was established. Under optimal conditions, the established method showed low limits of detection (0.002-0.1 ng mL-1), satisfactory recoveries (84.1-97.7%) and good repeatability (relative standard deviation (RSD) below 9%). The method was successfully verified using wastewater, urine and cocktail samples. Recoveries of SCs at three spiking levels were in the range of 75.1-98.6%, with RSD values below 7.0%. Compared with commercial sorbents, DMIPs showed better clean-up ability with matrix effect values of -24.1%-8.3% for all SCs in wastewater, urine and cocktail samples. Therefore, the developed DMIPs-SPE-HPLC-MS/MS strategy could be used as a specific and cost-effective method for sensitive determination of SCs in complex samples.