Specific recognition and solid phase extraction of three primary aromatic amines based on molecularly imprinted polymer monolith for the migration detection in food contact materials

A molecularly imprinted polymer (MIP) monolith was in situ synthesized in pipette tip with 4,4′-methylenedianiline (4,4′-MDA) as template molecule and 4-vinylpyridine as functional monomer. The 4,4′-MDA-MIP monolith was used to extract three primary aromatic amines (PAAs), including 4,4′-MAD, 4-aminobiphenyl and 3,3′-dichlorobenzidine. The 4,4′-MDA-MIP monolith have specific recognition capacity and high adsorption capacity for the three PAAs. The imprinting factor for 4,4′-MAD was up to 4.26 and the adsorption capacity for 4-aminobiphenyl was up to 117.94 mg g−1. The extraction parameters for the pipette tip solid-phase extraction (PTSPE) were optimized. A determination method for the three PAAs was established by coupling the PTSPE with high performance liquid chromatography-diode array detector. The detection linear range (LRs) was 0.70–500 µg kg−1 (R2 > 0.998), and the limits of detection (LODs) was 0.23–1.00 µg kg−1 (S/N = 3). The method was used for the migration detection of the PAAs from four polypropylene spoons, which showed satisfactory recovery of 87.4–110.6 %, indicating that the 4,4′-MDA-MIP monolith had good enrichment ability for PAAs in a complex matrix.