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In this communication, we demonstrate for the first time that ultrathin graphitic carbon nitride (g-C₃N₄) nanosheets can serve as a low-cost, green, and highly efficient electrocatalyst toward the reduction of hydrogen peroxide. We further demonstrate its application for electrochemical glucose biosensing in both buffer solution and human serum medium with a detection limit of 11 μM and 45 μM, respectively.

The present communication demonstrates the proof of concept of using CoFe layered double hydroxide (CoFe-LDHs) nanoplates as an effective peroxidase mimetic to catalyze the oxidation of peroxidase substrate 3,3',5,5'-tetramethylbenzidine in the presence of H(2)O(2) to produce a blue solution. We further demonstrate successfully CoFe-LDHs nanoplate-based colorimetric assay to detect H(2)O(2) and glucose.

The present paper reports on the first preparation of 2,4,6-tris(2-pyridyl)-1,3,5-triazine nanobelts (TPTNBs) by adjusting the pH value of the solution and the subsequent synthesis of Ag nanoparticle (AgNP)-decorated TPTNBs (AgNP-TPTNBs) by mixing an aqueous AgNO(3) solution with preformed TPTNBs without use of any external reducing agent. It is found that the resultant AgNP-TPTNBs exhibit notable catalytic performance for H(2)O(2) reduction. A glucose biosensor was fabricated by immobilizing glucose oxidase (GOD) onto a AgNP-TPTNBs-modified glassy carbon electrode (GCE) for glucose detection. The constructed glucose sensor has a wide linear response range from 3 mM to 20 mM (r: 0.999) with a detection limit of 190 μM. It is further shown that this glucose biosensor can be used for glucose detection in human blood serum.

The article demonstrates the application of graphene flakes (GFs) as supercapacitors. It discusses the preparation of electrode materials by hydrothermal synthesis. It reports that GFs synthesized through chlorosulfonic acid and hydrogen peroxide exfoliation have been successfully used to synthesize a manganese oxide/GF (MG) composite. It adds that GFs exhibit good conductivity and inhibit the aggregation of the manganese oxide nanosheets.

Abstract: In this paper, we report on one-pot synthesis of Ag nanoparticles/reduced graphene oxide (AgNPs/rGO) nanocomposites by heating mixed solution of graphene oxide (GO) and AgNO3 with the use of diethylenetriamine as a reducing agent at 80°C for 30min. Several analytical techniques including UV–vis spectroscopy, Raman spectroscopy and transmission electron microscopy (TEM) have been employed to characterize the resulting nanocomposites. It was found that such nanocomposites exhibit good catalytic activity toward the reduction of H2O2. This nonenzymatic H2O2 sensor shows a fast amperometric response time of less than 2s. The linear detection range is estimated to be from 0.1 to 100mM (r =0.999), and the detection limit is estimated to be 3.6μM at a signal-to-noise ratio of 3. [Copyright &y& Elsevier]

Abstract: Ag nanoparticles-decorated reduced graphene oxide (AgNPs-rGO) has been successfully fabricated through a one-step strategy, carried out by hydrothermal treatment of the mixture of AgNO3 and GO solution under strong alkaline conditions at 180°C for 30min. The reaction was accomplished without extra reducing agent and surface modifier. As-synthesized AgNPs-rGO has been successfully applied in catalytic performance toward the reduction of H2O2. This H2O2 sensor shows a wide linear range of 0.1–60mM (r =0.991) and a low detection limit of 1.80μM at a signal-to-noise ratio of 3. [Copyright &y& Elsevier]

Abstract: The present communication reports a novel and simple strategy to synthesize Au nanoplates (AuPs) by heating an aqueous solution of HAuCl4 in the presence of poly [(2-ethyldimethylammonioethyl methacrylate ethyl sulfate)-co-(1-vinylpyrrolidone)] (PQ11). Direct placing of the resultant dispersion on a glassy carbon electrode (GCE) surface gives a very stable AuPs-containing film exhibiting remarkable catalytic performance toward both the oxidation and reduction of H2O2. This enzymeless H2O2 sensor shows a fast amperometric response time of less than 3s and the corresponding linear range and detection limit are estimated to be from 0.1mM to 50mM (r =0.999) and 4μM at a signal-to-noise ratio of 3, respectively. [Copyright &y& Elsevier]