Analytica Chimica Acta 650 (2009) 195–201 Contents lists available at ScienceDirect Analytica Chimica Acta journal homepage: www.elsevier.com/locate/aca Use of a bisphenol-A imprinted polymer as a selective sorbent for the determination of phenols and phenoxyacids in honey by liquid chromatography with diode array and tandem mass spectrometric detection E. Herrero-Hernández 1 , R. Carabias-Martínez, E. Rodríguez-Gonzalo ∗ Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Química, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca, Spain article info Article history: Received 26 May 2009 Received in revised form 15 July 2009 Accepted 15 July 2009 Available online 21 July 2009 Keywords: Molecularly imprinted polymer Bisphenol-A Phenols Phenoxyacids Molecularly imprinted solid phase extraction Honey abstract An extraction-preconcentration procedure based on the use of a molecularly imprinted polymer (MIP) as selective sorbent has been developed for the determination of several phenolic compounds (bisphenol- A, bisphenol-F and 4-nitrophenol) and phenoxyacid herbicides (2,4-D, 2,4,5-T and 2,4,5-TP) in honey samples. Liquid chromatography with diode array detection (LC–DAD) and electrospray ionisation-ion trap mass spectrometry (LC–IT-MS) were used for the separation, identification and quantification of these analytes. The molecularly imprinted polymer was obtained by precipitation polymerisation with bisphenol-A (BPA) as template and 4-vinylpyridine as the functional monomer. The behaviour of this sorbent was compared with those of other materials frequently used in SPE. The selectivity of the BPA–MIP for the target analytes was tested in samples containing other pesticides in common use. The recoveries achieved for all six compounds were in the 81–96% range. By applying the proposed procedure prior to LC–IT-MS, the limits of detection achieved in commercial honey samples were in the 0.1–3.8 ng g -1 range, with relative standard deviations of 12–24%. © 2009 Elsevier B.V. All rights reserved. 1. Introduction Honey is a wholesome natural product consumed all over the world. The nutritional and quality aspects of honey are important since they determine consumer acceptance. The safety of honey is also critical because it affects human health and hence there is increasing interest in monitoring honey for the presence of pesti- cides and other chemical compounds. According to European Union (EU) regulations, honey as a natural product must be free of chem- icals [1]. The global evaluation of honey requires the study of possi- ble contamination by harmful substances. According to EC norm 2001/110/EC (2002), honey must be free of antibiotics, pesticides, atmospheric pollutants and heavy metals [2]. European Union (EU) legislation has established a level of 0.01 mg kg -1 as the general limit applicable “by default” as the maximum pesticide residue level in food products for human consumption [Regulations EC no 396/2005 and no 178/2006]. ∗ Corresponding author. Tel.: +34 923 294 483; fax: +34 923 294 483. E-mail address: erg@usal.es (E. Rodríguez-Gonzalo). 1 Present address: Institute of Natural Resources and Agrobiology (IRNASA-CSIC), Salamanca 37008, Spain. Owing to the complex nature of the matrices in which the target compounds are present, efficient sample preparation and trace-level detection and identification are important aspects of analytical methods. At present, solid-phase extraction (SPE) rep- resents a suitable way to extract, clean and preconcentrate target analytes from environmental or food samples. However, one prob- lem associated with ordinary SPE is its low selectivity, due to many unwanted interfering substances of similar hydrophobic- ity/hydrophilicity. Molecularly imprinted polymers (MIPs) are extensively cross- linked polymers containing specific recognition sites with a predetermined selectivity for analytes of interest. In recent years, molecularly imprinted polymers have been successfully used as selective sorbents in solid-phase extraction; the so called molec- ularly imprinted solid phase extraction (MISPE). Besides their selectivity, some qualities of MIPs, such as tolerance to extreme pH values and organic environments, have brought MIPs to the fore- front in contemporary chemical research. Owing to the inherent selectivity provided by these materials, MIPs have been considered as powerful sorbents for the extraction and clean-up of target ana- lytes in complex samples. Accordingly, the use of MISPE seems to represent an appropriate alternative to circumvent the drawback of more traditional SPE techniques, and it is particularly suitable for extractive applications where analyte selectivity represents the main problem. 0003-2670/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.aca.2009.07.043