ZIF-12-derived nitrogen doped porous carbon nanosheets-functionalized with silver nanoparticles for ratiometric molecularly-imprinted electrochemical sensing of D-penicillamine

[Display omitted] •A novel nanocomposite was fabricated for ratiometric electrochemical sensing of D-pencillamine.•The sensor consists of N@PCNS derived from ZIF-12 in the presence of saturated solution of zinc sulfate.•Addition of Ag improves conductivity and surface area; in addition, it acts as internal reference.•Advantages of the sensor are low LOD values, reproducibility, satisfactory stability, and selectivity.•It was applied to detect D-pencillamine in tablets and human serum/urine samples. In this work, an electrochemical platform was developed for detection of D-pencillamine utilizing highly responsive molecularly imprinted polymers (MIPs). This platform operates on a ratiometric principle and is constructed on nitrogen-doped porous carbon nanosheets (N-PCNS) derived from zeolite imidazolate frameworks (ZIF-12) in the presence of saturated solution of zinc sulfate. Subsequently, silver nanoparticles (Ag) were introduced onto the surface of N-PCNS/GCE to enhance conductivity and surface area, and serve as a standard signal. The MIP layer was formed on the Ag@N-PCNS/GCE surface through o-phenylenediamine (o-phen) electro-polymerization in the presence of the D-pencillamine (D-PAN) as a template. Detection of D-PAN relies on measuring ID-PAN/IAg response ratio employing differential pulse voltammetry (DPV). This ratio exhibits a linear correlation with the concentration of D-PAN in the dynamic linear range of 0.161–170 µM, exploiting LOD of 38.0 nM (S/N = 3). The electrochemical sensor offers numerous advantages including low detection limit, accuracy, stability, and sufficient degree of selectivity. Utilizing this platform, D-PAN-containing samples were efficiently analyzed with recovery percentages of 98.0–102.0 % and RSDs of 2.78–3.89 %, demonstrating the accuracy of the method.