Pioneering adsorption-assisted electrochemical polymerization approach for the fabrication of an acetaminophen sensor: experimental and theoretical studies

The fabrication of a polymelamine (PM)-modified glassy carbon electrode (GCE) <i>via</i> an innovative adsorption-assisted electropolymerization approach (EPM/GCE) for the detection of acetaminophen is presented in this study. Electrooxidation of ACE at EPM/GCE and another PM-modified GCE produced through the conventional electrodeposition approach (CPM/GCE) showed that the EPM/GCE possessed superior electrocatalytic activity toward ACE oxidation. Investigation of the impact of ACE concentration on the peak current showed that ACE concentration was linear over the range of 1.58-7.86 and 15.57-158.8 µM. The limit of detection (LOD) for ACE at the EPM/GCE was estimated from the lower linear range as 1.46 µM. ACE electroanalysis in a drug sample showed a progressive increase in ACE concentration with drug dosage, while the percentage recovery of ACE from the wastewater sample was 92%. The increase in the peak current of ACE with an increase in ACE concentration in the presence of ciprofloxacin (CFX) showed that the proposed sensor is capable of ACE determination in the presence of another drug sample. Simulation of the adsorption of ACE and CFX on the proposed sensor (represented by melamine) revealed that it has a greater affinity for CFX than ACE, suggesting its suitability for CFX determination in addition to ACE. Density functional theory (DFT) calculations also confirmed the suitability of melamine for GCE modification. Adsorption simulations revealed that the affinity of the proposed sensor for CFX is due to the higher reactivity of CFX than that of ACE. EPM/GCE showed remarkable repeatability, reproducibility and stability, confirming its great potential for routine drug analysis in real-life samples.