Non-enzymatic ultrasensitive electrochemical detection of acetaminophen in urine using novel metal-organic framework anchored graphite rod electrode

Acetaminophen (AP) is used to a large extent as a pain relief drug worldwide. Now a days AP is present in high concentrations in water resources and also found in the human blood. Therefore, it is of utmost importance to detect AP for the benefit of human health. In order to obtain low-cost and highly sensitive and selective sensors for AP detection, in the present investigation, we developed a novel free-standing electrochemical sensor. We adopted the synthesis process via a facile, mild one-step solvothermal technique and developed Ni(BPDC)MOF/GRP. Inter-connected Ni(BPDC)MOF/GRP sheets provide a large external area, huge pore volume and copious reactive spots, which show extensive interactive capacity towards AP. Block-shaped MOF-anchored GRP electrode enhances electrooxidation of adsorbed AP molecules due to superior electrocatalytic properties and electronic conductivity. As-prepared MOF hybrid rod was well characterized and analyzed by various characterization practices like FTIR, Raman spectra, XRD, XPS, BET, FESEM with energy dispersive spectrometry (EDS) mapping, and HRTEM etc. The electrochemical properties of proposed hybrid electrode studied by Cyclic Voltammetry (CV), Differential Pulse Voltammetry (DPV), impedance spectroscopy and chrono-amperometry methods. The Ni(BPDC)MOF/GRP electrode exhibited a linear detection region (LDR) from 2.5 to 100 μM, a limit of detection (LOD) of 0.056 μM and limit of quantification (LOQ) of 0.169 μM. An acceptable recovery rate ranging from 95.6 % to 104.2 % was achieved by using the proposed sensor to evaluate AP in spiked human urine serum samples. Therefore, the sensor electrode offers a simple, affordable, eco-friendly, and portable solution for AP detection.