A piezogravimetric sensor platform for sensitive detection of lead (II) ions in water based on calix[4]resorcinarene macrocycles: Synthesis,characterization and detection

The heavy metal ions detection is a foremost concern in water sources, the conventional detection methods are either time consuming or expensive, thus the need of fast, low-cost and accurate sensing methods is growing. Based on this direction, this paper describes the synthesis of newly enantiomeric calix4]resorcinarenes, namely: C-dec-9-enylcalix4]resorcinarene-O-(S-)-α-methylbenzylamine (Compound B) and C-dec-9-enylcalix4]resorcinarene-O-(R+)-α-methylbenzylamine (Compound C), the two macrocycles were the subject of comparative characterization studies using (FTIR, ¹H NMR, ¹³C NMR, TG-DSC-MS, and P-XRD). The realization of modified quartz resonator-gold electrodes, and its introductory employment in the assembly of a novel QCM-I (Quartz Crystal Microbalance with Impedance measurements) based chemosensor for the detection of lead ions in the aqueous solutions is reported for the first time to the best of our knowledge, moreover both Calix-QCM based sensors presented good linearity, acceptable sensitivities, and wide linear ranges, as well as lower detection limits in the order of 0.45 and 0.30 ppm for compounds B and C, consecutively.