Detection of biogenic amines using calixarene coated QCM sensors

In this study, it was aimed to prepare QCM sensors coated with calix[4]arene derivatives bearing different functional groups and to determine their sensing properties in aqueous media for biogenic amines, which are known to be precursors of carcinogenic and/or mutagenic agents in various food products, in QCM system. For this purpose, calix[4]arene derivatives (K-3, K-4, K-5, K-6 and K-7) used as sensing materials were first synthesized and their structures were confirmed using 1H-NMR and FT-IR spectroscopy methods. Then, calix[4]arene derivatives were coated on the surface of QCM crystals by solution retention method and calix[4]arene coated QCM sensors were prepared. The sensing properties of the QCM sensors against different biogenic amines (tryptamine (TRI), tyramine (TIR), spermidine (SPD), spermine (SPM), cadaverine (KAD), and histamine (HIS)) in aqueous media were investigated. As a result of the sensing studies, among the QCM sensors coated with calix[4]arene derivatives, the calix[4]arene derivative (K-4) coated QCM (K4-QCM) sensor containing aldehyde group was found to be the best QCM sensor against all biogenic amines studied. According to the frequency changes, the K4-QCM sensor exhibited the highest response to SPM and the LOD value for SPM was calculated as 2.4×10-5 M. According to the stoichiomeric ratio (SO) values, it was observed that the K4-QCM sensor reached the highest SO value in case of KAD and the LOD value for KAD was calculated as 2.0×10-5 M. It was evaluated that hydrogen bonding interactions between calixarene molecules and biogenic amine molecules and molecular weight or size play an important role in the emergence of the most efficient sensor:analyte pair. Isotherm parameters of the K4-QCM sensor for SPM and KAD were determined and adsorption behaviors were evaluated. Reproducibility studies of the K4-QCM sensor for SPM and KAD showed that the sensor gave reproducible results. The results of the study are promising for the development of QCM sensors coated with different calixarene derivatives for the detection of different biogenic amines or different analytes.