Integrative application of biochar and bacteria for mitigating antimony toxicity and bio-accessibility in sorghum.

Antimony (Sb) toxicity is a serious concern due to its harmful effects on humans and plants. Biochar (BC) has become a popular amendment for remediating soils polluted with metals and metalloids. However, the exact interaction mechanism between BC, and microbes to remediate Sb-polluted soils remains unclear.

Efficient Adsorption and Electrochemical Detection of Cd with a Ternary MgZnFe-Layered Double Hydroxides Engineered Porous Biochar Composite.

Their unique layered structure, large specific surface area, good stability, high negative charge density between layers, and customizable composition give layered double hydroxides (LDHs) excellent adsorption and detection performance for heavy metal ions (HMIs). However, their easy aggregation and low electrical conductivity limit the practical application of untreated LDHs. In this work, a ternary MgZnFe-LDHs engineered porous biochar (MgZnFe-LDHs/PBC) heterojunction was proposed as a sensing and adsorption material for the effective detection and removal of Cd from wastewater.

In Situ Synthesis of MnMgFe-LDH on Biochar for Electrochemical Detection and Removal of Cd in Aqueous Solution.

Herein, MnMgFe-layered double hydroxides/biochar (MnMgFe-LDHs/BC) composite was fabricated by immobilizing MnMgFe-LDHs on BC via the coprecipitation method, which was employed as an effective material for the detection and removal of Cd from aqueous media. A lamellar structure of MnMgFe-LDHs with abundant surface-hydroxyl groups and various interlayer anions inside present a greater chance of trapping Cd. Meanwhile, the conductive BC with a porous structure provides numerous channels for the adsorption of Cd.

Core-shell Cu@C@ZIF-8 composite: a high-performance electrode material for electrochemical sensing of nitrite with high selectivity and sensitivity.

Herein, an efficient electrochemical sensing platform is proposed for selective and sensitive detection of nitrite on the basis of Cu@C@Zeolitic imidazolate framework-8 (Cu@C@ZIF-8) heterostructure. core-shell Cu@C@ZIF-8 composite was synthesized by pyrolysis of Cu-metal-organic framework@ZIF-8 (Cu-MOF@ZIF-8) in Ar atmosphere on account of the difference of thermal stability between Cu-MOF and ZIF-8. For the sensing system of Cu@C@ZIF-8, ZIF-8 with proper pore size allows nitrite diffuse through the shell, while big molecules cannot, which ensures high selectivity of the sensor.

MXene/carbon nanohorns decorated with conductive molecularly imprinted poly(hydroxymethyl-3,4-ethylenedioxythiophene) for voltammetric detection of adrenaline.

A novel molecularly imprinted sensor was developed for the voltammetric determination of adrenaline (AD). MXene/carbon nanohorn (MXene/CNH) composite with good electric conductivity and enormous accessible active sites was firstly introduced as catalytic substrate. Subsequently, molecularly imprinted polymer (MIP) film was fabricated in mixed solutions containing hydroxymethyl-3,4-ethylenedioxythiophene (functional monomer) and AD (template) through electro-polymerization process.

MXene@Ag-based ratiometric electrochemical sensing strategy for effective detection of carbendazim in vegetable samples.

In this paper, a novel ratiometric electrochemical sensor for carbendazim (CBZ) detection was constructed by a composite of MXene@Ag nanoclusters and amino-functionalized multi-walled carbon nanotubes (MXene@AgNCs/NH-MWCNTs). The Ag nanoclusters (AgNCs) embedded in the MXene not only could inhibit the aggregation of MXene flakes and enhance the electrocatalytic ability, but also serve as an internal reference probe for the ratiometric electrochemical detection. Moreover, the introduction of NH-MWCNTs can further improve the electrochemical signals of CBZ and Ag, resulting in the enhanced signal amplification and higher sensitivity.

TiCTMXene/nitrogen-doped reduced graphene oxide composite: a high-performance electrochemical sensing platform for adrenaline detection.

Herein, TiCTMXene/N-doped reduced graphene oxide (MXene/N-rGO) composite was employed as the electrocatalyst to construct a new electrochemical sensing platform for the determination of adrenaline (AD). The MXene/N-rGO was synthesized via a facile one-step hydrothermal method, where ethylenediamine acted as a reducing agent and N source. The doped N in rGO served as a bridge between MXene and rGO through tight hydrogen bonds.

Prussian blue-carboxylated MWCNTs/ZIF-67 composite: a new electrochemical sensing platform for paracetamol detection with high sensitivity.

In this study, the composite of Prussian blue-carboxylated MWCNTs/ZIF-67 (PB-MWCNTs-COOH/ZIF-67) was synthesized and used as modified electrode material to fabricate an electrochemical sensor for the determination of paracetamol (PAR). In this sensor system, negatively charged MWCNTs-COOH as support for the immobilization of positively charged PB can effectively avoid the agglomeration of PB and enhance the stability, conductivity and catalytic activity of the composite. ZIF-67 particles coating outside PB-MWCNTs-COOH promotes the concentration of PAR.

Sensitive electrochemical platform for trace determination of Pb based on multilayer Bi-MOFs/reduced graphene oxide films modified electrode.

A multilayer Bi-BTC/reduced graphene oxide (Bi-BTC/rGO) (BTC, 1,3,5-benzenetricarboxylic acid) film electrode was adopted to construct a highly sensitive Pb electrochemical sensor. The multilayer Bi-BTC/rGO films were prepared via alternate cast of Bi-BTC and graphene oxide (GO) on a glassy carbon electrode, followed by electro-reduction of the GO components. Bi-BTC has porous broom-like structure and its organic ligand has abundant functional groups, which are favorable for Pb adsorption and preconcentration.

[Comparison of edge fitness and metal-ceramic bonding force of base metal crowns performed using two methods].

Purpose: To compare the marginal fitness and metal-ceramic bonding strength between laser printing metal crown and cast cobalt-chromium alloy crown.

Methods: Cobalt-chromium alloy crowns (n=10)(group A) were made by laser printing and another 10 by traditional casting (group B), respectively. All the first molar crowns were metal substitutes, and the basal crowns were placed in the standard substitutes.

Mxene/carbon nanohorn/β-cyclodextrin-Metal-organic frameworks as high-performance electrochemical sensing platform for sensitive detection of carbendazim pesticide.

Pesticides play an important role in agricultural fields, but the pesticide residues pose strong hazardous to human health, thus designing sensitive and fast method for pesticides monitor is highly urgent. Herein, nanoarchitecture of Mxene/carbon nanohorns/β-cyclodextrin-Metal-organic frameworks (MXene/CNHs/β-CD-MOFs) was exploited as electrochemical sensing platform for carbendazim (CBZ) pesticide determination. β-CD-MOFs combined the properties of host-guest recognition of β-CD and porous structure, high porosity and pore volume of MOFs, enabling high adsorption capacity for CBZ.

NiO@Ni-MOF nanoarrays modified Ti mesh as ultrasensitive electrochemical sensing platform for luteolin detection.

A novel electrochemical sensor was constructed based on three-dimensional NiO@Ni-MOF nanoarrays modified Ti mesh (NiO@Ni-MOF/TM). NiO nanoarrays were firstly produced on conductive TM using hydrothermal and carbonization method, and then Ni-MOFs were directly grown on the surface of NiO nanoarrays through self-template strategy. The morphology and structure of the prepared materials were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS).

Self-template synthesis of flower-like hierarchical graphene/copper oxide@copper(II) metal-organic framework composite for the voltammetric determination of caffeic acid.

Flower-like graphene/CuO@Cu-BTC (GR/CuO@Cu-BTC) composite was employed as electrode material for the voltammetric determination of caffeic acid (CA) in the wine. The composite material was prepared via the self-template method. In this synthetic process, budlike CuO not only acts as the template, but also provides Cu ions for in situ growth of the Cu-BTC shell.

A poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)-based electrochemical sensor for tert.-butylhydroquinone.

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is a readily available copolymer that comes as an aqueous dispersion with good processability. A flexible voltammetric sensor for the widely used food stabilizer tert.-butylhydroquinone (TBHQ) was constructed by using a film of PEDOT:PSS.

Ratiometric electrochemical sensor for sensitive detection of sunset yellow based on three-dimensional polyethyleneimine functionalized reduced graphene oxide aerogels@Au nanoparticles/SH-β-cyclodextrin.

Electrochemical methods have been deemed effective strategies for the detection of dye additive sunset yellow (SY) owing to their low cost, good stability, and high sensitivity. However, the application of the existing sensors with single electrical signal response is limited by their inadequate sensitivity and large background interference. Herein, a ratiometric electrochemical strategy with a dual signal was developed to detect SY.

A CuO-CeO composite prepared by calcination of a bimetallic metal-organic framework for use in an enzyme-free electrochemical inhibition assay for malathion.

An enzyme-free electrochemical method is described for the determination of trace levels of malathion. It is based on a nanostructured copper-cerium oxide (CuO-CeO) composite prepared by calcination of a Cu(II)/Ce(III) metal-organic framework. The morphology, crystal structure and elemental composition of composite was studied by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy.

Graphene-derived nanomaterials as recognition elements for electrochemical determination of heavy metal ions: a review.

This review (with 155 refs.) summarizes the progress made in the past few years in the field of electrochemical sensors based on graphene-derived materials for the determination of heavy metal ions. Following an introduction of this field and a discussion of the various kinds of modified graphenes including graphene oxide and reduced graphene oxide, the review covers graphene based electrodes modified (or doped) with (a) heteroatoms, (b) metal nanoparticles, (c) metal oxides, (d) small organic molecules, (e) polymers, and (f) ternary nanocomposites.

High-performance voltammetric sensor for dichlorophenol based on β-cyclodextrin functionalized boron-doped graphene composite aerogels.

2, 2-methylenebis (4-chlorophenol) (dichlorophenol, Dcp) is a priority pollutant that poses a serious health threat to the public. Thus, the sensitive analysis of Dcp is of great significance. Heteroatom-doped carbon nanomaterials modified electrodes have been proven to be good electrocatalysts for electrochemical sensing application.

Aerogels prepared from polymeric β-cyclodextrin and graphene aerogels as a novel host-guest system for immobilization of antibodies: a voltammetric immunosensor for the tumor marker CA 15-3.

A three-dimensional porous network graphene aerogel (GAs) with large specific area and excellent conductivity was loaded with β-cyclodextrin polymer (Pβ-CD) to serve as a support for immobilization of antibodies. A highly sensitive immunosensor for the cancer marker carbohydrate antigen 15-3 (CA15-3) was designed based on the use of Pβ-CD/GAs. The large specific area of GAs warrants high loading with antibodies, and their excellent electrical conductivity warrants strong electrical signals.

Simple and green synthesis of piperazine-grafted reduced graphene oxide and its application for the detection of Hg(II).

In this paper, piperazine-grafted reduced graphene oxide (NH-rGO) was synthesized via a simple and green two-step procedure: (i) opening of the resulting epoxides of graphene oxide (GO) with piperazine (NH) through nucleophilic substitution; (ii) reduction of GO with ascorbic acid. Its structure and morphology were characterized by scanning electron microscopy and x-ray photoelectron spectroscopy. The NH-rGO modified glassy carbon electrode was explored as an electrochemical sensor for the determination of Hg(II) using a differential pulse anodic stripping voltammetry technique.

Label-free electrochemical immunosensor based on Nile blue A-reduced graphene oxide nanocomposites for carcinoembryonic antigen detection.

In this article, a novel, label-free, and inherent electroactive redox immunosensor for carcinoembryonic antigen (CEA) based on gold nanoparticles (AuNPs) and Nile blue A (NB) hybridized electrochemically reduced graphene oxide (NB-ERGO) is proposed. The composite of NB-graphene oxide (NB-GO) was prepared by π-π stacking interaction. Then, chronoamperometry was adopted to simultaneously reduce HAuCl4 and nanocomposites of NB-GO for synthesizing AuNPs/NB-ERGO.

An enhanced electrochemical platform based on graphene oxide and multi-walled carbon nanotubes nanocomposite for sensitive determination of Sunset Yellow and Tartrazine.

A novel electrochemical platform was designed for the simultaneous determination of Sunset Yellow (SY) and Tartrazine (TT), synthetic food dyes, by combining the signal amplification properties of graphene oxide (GO) and the excellent electronic and antifouling properties of multi-walled carbon nanotubes (MWCNTs). Stable dispersion of GO/MWCNTs composite was produced by sonication mixing. Compared with glassy carbon, MWCNTs and GO electrodes, GO/MWCNTs electrode exhibited strong enhancement effect and greatly increased the oxidation signal of SY and TT.