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A composite film of nickel hexacyanoferrate (NiHCF) and bentonite (Bt) clay (abbreviated as NiHCF−Bt) is synthesized by an in situ electrochemical method. For this synthesis, nickel ions are immobilized on Bt clay by an ion‐exchange process, equilibrating Bt clay with nickel nitrate. On a glassy carbon electrode (GCE), the nickel ion‐exchanged Bt clay (Ni2+−Bt) is coated to get the modified electrode which is represented as GCE/Ni2+−Bt. The NiHCF−Bt composite film is prepared on the GCE surface using the GCE/Ni2+−Bt and scanning the electrode potentials between −0.10 to 1.00 V continuously in an aqueous solution containing potassium hexacyanoferrate and potassium chloride. This NiHCF−Bt modified GCE (GCE/NiHCF−Bt) exhibits redox peaks due to the oxidation and reduction of the central metal ion, Fe2+. The electro‐generated Fe3+ present in the GCE/NiHCF−Bt, electrocatalytically oxidizes a range of drugs like acetaminophen (AC), dopamine (DA), and tyrosine (TY) at decreased overpotentials with high current. This property is advantageously used for the precise quantification of AC, DA, and TY. Sensitivity, limit of detection, and linear calibration range for the determination of AC are found to be 0.20 μA μM−1 cm−2, 1.5 μM, and 25.0–1000.0 μM, respectively. Further, the amount of AC present in pharmaceutical products is satisfactorily quantified which demonstrated the use of the NiHCF−Bt composite film in electroanalysis. [ABSTRACT FROM AUTHOR]

MnO2 nanorods incorporated MCM‐41 nanocomposite (MnO2@MCM‐41) is synthesized and employed as an electrode modifier for individual as well as simultaneous detection of purine bases, guanine (GU) and adenine (AD). For this purpose MnO2 nanorods are encapsulated within MCM‐41 by simple one pot synthetic approach. FT‐IR, UV‐vis absorption spectroscopy, scanning electron microscopy, energy dispersive X‐ray spectroscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy and electrochemical methods are employed to characterize the nanocomposite and other materials. The electrochemical attributes of glassy carbon electrode (GCE) modified with the MnO2@MCM‐41 (represented as GCE/MnO2@MCM‐41) towards the determination of GU and AD is studied in detail. Upon incorporation of MnO2 nanorods on MCM‐41, noticeable upsurge in anodic peak current with a decline in peak potential is observed for both GU and AD oxidations in cyclic voltammetry studies. Individual as well as simultaneous determination of GU and AD are performed using differential pulse voltammetry (DPV) technique which offered a linear range of 100 nM to 100 μM for GU and AD with respective limit of detections, 44 and 66 nM. The practical applicability of the GCE/MnO2@MCM‐41 for real world samples analysis is satisfactorily demonstrated with certain DNA samples by DPV. [ABSTRACT FROM AUTHOR]