Electrochemical Sensor for Ascorbic Acid, Acetaminophen and Nitrite Based on Organoclay/Zr‐MOF Film Modified Glassy Carbon Electrode

A composite (Sa‐HTDMA/UiO‐66) consisting of organoclay (Sa‐HTDMA) and a metal‐organic framework (UiO‐66) was prepared using organically modified natural Cameroonian clay and Zr‐MOF. The organoclay was obtained by intercalating in its interlayer hexadecyltrimethyl ammonium cation (HTDMA). The composite was then used to form a film onto a glassy carbon electrode (GCE) by drop coating (Sa‐HTDMA/UiO‐66/GCE). Electrochemical responses recorded at the as‐prepared modified electrodes for ascorbic acid (AA), acetaminophen (AC) and nitrite (NO 2 − ) were investigated using cyclic and linear sweep voltammetry. The results revealed that Sa‐HTDMA/UiO‐66/GCE exhibited a favorable behavior for individual and simultaneous sensing of AA, AC and NO 2 − . Additionally, compared with UiO‐66 modified GCE, the composite enabled good performance of the electrode. Under the optimum conditions, the linear calibration curves were attained in the following ranges: 1–650 μM for AA, 1–700 μM for AC and 1–600 μM for NO 2 − with the respective detection limits of 0.01, 0.19 and 0.33 μM. Application of the sensors to determine AA and AC in pharmaceutical preparations, and NO 2 − in tap water, was successful.