Sensitive detection of bisphenol A in complex samples by in-column molecularly imprinted solid-phase extraction coupled with capillary electrophoresis

•We developed an in-column molecularly imprinted SPE system coupled with CE.•Sensitive detection method for bisphenol A.•Good analytical performance with a low detection limits (0.8 ng mL− 1) and recovery.•The proposed system provides the advantages of on-line extraction and desorption.

An on-line molecularly imprinted solid-phase extraction (MISPE) method was developed for the capillary electrophoresis (CE) detection of bisphenol A (BPA). Analyte extraction was achieved by using an in-column MISPE concentrator, which was prepared by coating the molecularly imprinted polymer (MIP) material directly in the separation capillary. The key parameters influencing the extraction efficiency, including the sample pH, extraction time, desorption solvent, and the injection duration of the desorption solution, were investigated. The combination of MISPE with CE produced a linear relationship between the CE peak areas versus the BPA concentration in the range from 3 to 300 ng mL− 1 with a limit-of-detection (LOD) as low as 0.8 ng mL− 1. The LOD of MISPE-CE is over 100-fold lower than that of direct CE determination. The MISPE-CE method was used for the analysis of four BPA-spiked samples: tap water, river water, a beverage, and urine, with recoveries in the range of 87.2–108.3%. The MISPE-CE method features the advantages of on-line extraction, ease of atomization, and low sample consumption.