Uric acid is mainly produced from metabolism of purine nucleotide in human body and have several medical importance in human system. It is therefore very imperative to develop a sensitive and accurate method of its detection. This study aimed to develop uric acid biosensor based on polydopamine/polypyrole (PDA/PPY) composite decorated on glassy carbon electrode. The conductive polymer PDA/PPY was electrochemically synthesized and casted on glassy carbon electrode (GCE). The synthesized PDA/PPY was characterized by fourier transform infrared spectroscopy, field emission scanning electron microscopy, electrochemical impedance spectroscopy, energy dispersive x‐ray spectroscopy and x‐ray photoelectron spectroscopy. PDA/PPY/GCE showed good response towards uric acid with low limit of detection (0.1 μM, S/N =3), good linearity (0.5‐40 μM) and high sensitivity (2.1 μAμMcm−2). It was also found to have stable response for uric acid unaffected by common interferents. Also, when used for uric acid detection in human serum and urine, it showed a good recovery of 90–110%. The developed PDA/PPY composite is proposed as a promising biosensor for uric acid for human health protection.

We describe non-enzymatic novel detection of nitrite ions in various matrices on the surface of poly-3-aminobenzoic acid.

Lead is a potentially toxic element (PTE) that has several adverse medical effects in humans. Its presence in the environment became prominent due to anthropogenic activities. The current study explores the use of newly developed composite materials (organic–inorganic hybrid) based on PANI-GO-APTES for electrochemical detection of Pb2+ in aqueous solution. The composite material (PANI-GO-APTES) was synthesized by chemical method and was characterized with SEM, XPS, XEDS, XRD, TGA, FTIR, EIS and CV. The result of characterization indicates the successful synthesis of the intended material. The PANI-GO-APTES was successfully applied for electrochemical detection of Pb2+ using cyclic voltammetry and linear sweep voltammetry method. The limit of detection of Pb2+ was 0.0053 µM in the linear range of 0.01 µM to 0.4 µM. The current response produced during the electrochemical reduction of Pb2+ catalyzed by PANI-GO-APTES was also very repeatable, reproducible and rapid. The application of PANI-GO-APTES-modified GCE in real sample analysis was also established. Therefore, PANI-GO-APTES is presented as a potential Pb2+ sensor for environmental and human health safety.

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Electroreduction of carbon dioxide (CO2) in a flow electrolyzer represents a promising carbon-neutral technology with efficient production of valuable chemicals. In this work, the catalytic performance of polycrystalline copper (Cu), Cu2O-derived copper (O­(I)­D-Cu), and CuO-derived copper (O­(II)­D-Cu) toward CO2 reduction is unraveled in a custom-designed flow cell. A peak Faradaic efficiency of >70% and a production rate of ca. −250 mA cm–2 toward C2+ products have been achieved on all the catalysts. In contrast to previous studies that reported a propensity for C2+ products on OD-Cu in conventional H-cells, the selectivity and activity of ethylene-dominated C2+ products are quite similar on the three types of catalysts at the same current density in our flow reactor. Our analysis also reveals current density to be a critical factor determining the C–C coupling in a flow cell, regardless of Cu catalyst’s initial oxidation state and morphology.