A Facile One-Pot Synthesis of Copper Sulfide-Decorated Reduced Graphene Oxide Composites for Enhanced Detecting of H2O2 in Biological Environments

Facile Fabrication of Mn2O3 Nanoparticle-Assembled Hierarchical Hollow Spheres and Their Sensing for Hydrogen Peroxide

In the present work, we described the facile hydrothermal fabrication of Mn2O3 nanoparticle-assembled hierarchical hollow spheres and their application for the electrochemical determination of hydrogen peroxide (H2O2). The composition and morphology of the as-prepared samples were well characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Because of the electrochemical responses toward H2O2, a novel nonenzymatic electrochemical sensor for the H2O2 determination based on Mn2O3 hollow spheres modified glassy carbon electrode was proposed. The electrochemical properties of the modified electrode were investigated by cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry. The modified electrode displayed distinct amperometric response to H2O2 in a wide concentration range 0.10-1276.5 μM, with a linear range of 0.10-126.5 μM and a detection limit of 0.07 μM (S/N = 3). It exhibited excellent analytical performance in terms of long-time stability, good reproducibility and acceptable anti-interference ability. In addition, it was applied for the H2O2 determination in real samples directly with acceptable accuracy and recovery, demonstrating its potential application in routine H2O2 analysis.

Carbon nanomaterial-based electrochemical biosensors: an overview

Carbon materials on the nanoscale exhibit diverse outstanding properties, rendering them extremely suitable for the fabrication of electrochemical biosensors. Over the past two decades, advances in this area have continuously emerged. In this review, we attempt to survey the recent developments of electrochemical biosensors based on six types of carbon nanomaterials (CNs), i.e., graphene, carbon nanotubes, carbon dots, carbon nanofibers, nanodiamonds and buckminsterfullerene. For each material, representative samples are introduced to expound the different roles of the CNs in electrochemical bioanalytical strategies. In addition, remaining challenges and perspectives for future developments are also briefly discussed.

Phase transformation fabrication of a Cu2S nanoplate as an efficient catalyst for water oxidation with glycine

The synthesis of semiconducting nanoplates (NPs) with defined crystal phase is of particular interest, especially their intriguing properties related to the size, shape, and crystal phase. Herein, a liquid-state transformation process from hexagonal-phase CuS NPs is employed to fabricate the cubic-phase Cu2S NPs. The CuS NPs were converted into Cu2S NPs but maintained the morphology. The Cu2S NPs exhibit better oxygen evolution reaction (OER) activity than CuS NPs. Furthermore, the OER activity of Cu2S NPs can be improved by the addition of a glycine (Gly) solution. The Cu2S NPs with Gly in a phosphate buffer solution exhibit excellent OER activity and durability, which approaches that of the best known commercial Ir/C (20%) nanocatalyst. In this work, a good strategy for fabricating a noble-metal-free OER catalyst has been proposed, which could provide insight into developing new water oxidation catalysts with high activity.

rGO quantum dots/ZnO hybrid nanofibers fabricated using electrospun polymer templates and applications in drug screening involving an intracellular H2O2 sensor

Throughout the years, reported intracellular H₂O₂ sensors just focused on unrelated measurements of intracellular H₂O₂ generated from the stimulus of Cd²⁺, ascorbic acid (AA) etc., leading to difficulty in data interpretation. Here, a novel reduced graphene oxide quantum dots (rGO QDs)/ZnO hybrid nanofibers-based electrochemical biosensor for the detection of intracellular H₂O₂ released from cancer and normal cells under the stimuli of the corresponding anticancer drugs permits a quantitative study of the interaction between the target drug compound and the cancer cell, which is suitable for candidate drug screening. Nylon 6/6 nanofibers are used as robust templates for the facile fabrication of novel rGO QDs/ZnO hybrid nanofibers via electrospinning followed by a step hydrothermal growth method. The as-made sensor was applied to determine H₂O₂ released from a prostate cancer cell (PC-3) versus a noncancerous cell (BPH-1) under the stimuli of the corresponding anticancer drugs (apigenin, antisense CK2αetc.). The amount of H₂O₂ released from the PC-3 cancer cell is about (320 ± 12) amol per cell and about (210 ± 6) amol per cell for the BPH-1 noncancerous cell under the stimuli of specific therapy drug antisense CK2α. These results demonstrate that the rGO QDs/ZnO hybrid nanofibers-based electrochemical biosensor can efficiently detect the distinct amounts of H₂O₂ released from cancer and noncancer cells.

An electrochemical sensor based on reduced graphene oxide and copper sulfide hollow nanospheres

A nonenzymatic sensor for the detection of hydrogen peroxide (H₂O₂) was fabricated with reduced graphene oxide (RGO) and copper sulfide hollow nanospheres (CuSHNs).

Synthesis of a flower-like CuS/ZnS nanocomposite decorated on reduced graphene oxide and its photocatalytic performance

CZS/rGO composites with enhanced photocatalytic activity have been synthesized. The results demonstrate that the CZS/rGO composites have enormous potential for photodegradation of organic pollutants. The enhanced mechanism was also explained.

Porous hollow CuS nanospheres with prominent peroxidase-like activity prepared in large scale by a one-pot controllable hydrothermal step

Porous hollow CuS nanospheres with a variety of sizes were fabricated by an innovative one-pot method based on a facile template-assisted hydrothermal approach at low temperatures. The as-prepared CuS nanospheres exhibited a very prominent intrinsic peroxidase-like activity.

H2S bubbles-assisted synthesis of hollow Cu2−xSeyS1−y/reduced graphene oxide nanocomposites with tunable compositions and localized surface plasmon resonance

Homogeneous hollow Cu_2−xSe_yS_1−y/rGO nanocomposites are controllably synthesized by a facile one-pot aqueous chemical approach via H₂S gas bubble templates at room temperature, using a nonhazardous reducing agent, ascorbic acid.

Controlled synthesis of CuS caved superstructures and their application to the catalysis of organic dye degradation in the absence of light

CuS caved superstructures with a variety of sizes and regular shapes were synthesized by an innovative one-pot method, which showed excellent catalytic properties evaluated by degradation of methylene blue (MB) without light.

Overview on in vitro and in vivo investigations of nanocomposite based cancer diagnosis and therapeutics

The nanodevices are synthesized using nanocomposites by the researchers around the globe. Most of their applications are related to in vivo visualization and therapy with anticancer drugs in the field of oncology.

A sensitive electrochemical aptasensor based on the co-catalysis of hemin/G-quadruplex, platinum nanoparticles and flower-like MnO2 nanosphere functionalized multi-walled carbon nanotubes

A sensitive thrombin electrochemical aptasensor is developed based on the co-catalysis of hemin/G-quadruplex, platinum nanoparticles and flower-like MnO₂ nanosphere functionalized multi-walled carbon nanotubes.

Functionalized lanthanide coordination polymer nanoparticles for selective sensing of hydrogen peroxide in biological fluids

The fluorescence of Phe/Tb CPNPs functionalized with CPBA (Phe/Tb-CPBA CPNPs) was selectively quenched upon the addition of H₂O₂.

Facile synthesis of nickel hydroxide–graphene nanocomposites for insulin detection with enhanced electro-oxidation properties

This study describes a facile and effective one-pot route to synthesize structurally uniform and electrochemically active nickel hydroxide–graphene nanocomposites (Ni(OH)₂–GN) and investigates the electrocatalytic activity toward the oxidation of insulin.

Non-enzymatic hydrogen peroxide electrochemical sensor based on a three-dimensional MnO2 nanosheets/carbon foam composite

Three dimensional MnO₂ nanosheets/carbon foam has been fabricated and they exhibit promising electrochemical sensing performance for nonenzymatic H₂O₂ detection.

Hydrophilic Cu2−xSe/reduced graphene oxide nanocomposites with tunable plasmonic properties and their applications in cellular dark-field microscopic imaging

We report a facile and green approach to fabricate Cu_2−xSe/rGO nanocomposites at room temperature, with tunable plasmonic properties as well as favorable biocompatibility, and exploit them for cell imaging in vitro.