Holmium-Molybdate Nanoparticle-Modified Carbon Paste Electrode for Electrocatalytic Detection of Paracetamol

Holmium tetra-molybdate nanoparticles have been employed for the first time to modify carbon paste electrodes, leading to the creation of an electrochemical sensor for the detection of paracetamol (PAR). These nanoparticles were synthesized using a straightforward, one-pot, organic-solvent-free hydrothermal method. FTIR, XPS, SEM/EDS, TEM, XRD patterns, and Raman spectra showed high crystallinity of the material, characteristic stretching vibrations with an empty part of the spectrum in the range of 750–450 cm–1, confirming the regular form of tetramolybdate, with a uniform distribution of components. The resulting material demonstrated very good electrocatalytic performance, with a 4.5 times decrease in the Rct value obtained in the EIS study, significant current promotion, and a decrease in the ΔE value resulting from CV measurements, which can be attributed to its unique size and morphology. The practical feasibility of nanomaterials in analytical applications was demonstrated through the development of an electrochemical sensor that was then used to establish a sensor platform for PAR detection. Under optimized square wave voltammetry (SWV) conditions, the sensor exhibited a wide linear range of 3–300 μM, a low limit of detection of 0.314 μM, and a sensitivity of 0.239 μA μM–1 cm–2. These findings, along with satisfactory sensitivity, stability, and repeatability, underscore the potential of this sensor for routine paracetamol analysis, shown through the determination of PAR in pharmaceutical samples with 99.72% to 101.92% recovery values. Effective practical application in real matrices highlights this material as a high-performance structure for the real-time monitoring of biologically active compounds and applications in medicinal analytical chemistry and the pharmaceutical industry.