A Highly Selective Potentiometric Sensor for Detection of Zn(II) in Petroleum Water Samples Using Carbon Paste Electrode Based on Molecular Imprinted Polymer

For the purpose of determining the presence of zinc(II) in petroleum water samples, a molecular imprinted polymer (MIP) based modified carbon paste potentiometric method was described. Methacrylic acid monomers and ethylene glycol dimethacrylate were used in the polymerization process to create the MIP. The generated imprinted polymer was evaluated using flame atomic absorption spectrometry, Fourier transform infrared spectroscopy (FT-IR), and proton nuclear magnetic resonance (H-1-NMR). It was then used as a sorbent for selective magnetic solid phase extraction of zinc(II) ion. Using MIP as a suitable neutral carrier, a label modified carbon paste electrode (MCPEs) that is highly selective to Zn(II) ions was created. For MCPEs (Sensors I and II), they demonstrated a linear concentration range from 1.0x10(-7) to 1.0x10(-1) mol L-1 with Nernstian slopes of 28.43 +/- 0.63 and 29.27 +/- 0.48 mV decade(-1) , respectively. The sensors (I) and (II) had lifetime of 97 and 115 days and response time of 7 and 5 s, respectively. The suggested electrodes were successfully applied in determining the Zn(II) ion concentrations in petroleum water samples. The outcomes were comparable to those from atomic absorption spectroscopy (AAS) in actual spiked petroleum water samples.