Scalable one-step fabrication of integrated electrode arrays for highly sensitive and portable carbendazim detection.

Highly sensitive and portable pesticide residues detection are indispensable for safeguarding food safety and environmental health. Herein, we introduce a one-step vacuum filtration strategy for the scalable production of cobalt-based conjugated coordination polymers (CoCCPs) electrode arrays, utilizing carboxylated single-walled carbon nanotubes (c-SWNTs) as bonding bridges (CoCCPs@c-SWNTs). Due to their abundant active sites and high conductivity, the CoCCPs@c-SWNTs arrays exhibit superior electrochemical performance (e.

Ultrasensitive carbon nanotube-bridged MXene conductive network arrays for one-step homogeneous electrochemical immunosensing of tumor markers.

Developing non-passivating and fully integrated electrode arrays for point-of-care testing of carcinoembryonic antigen (CEA) is crucial, as the serum level of CEA is closely associated with colorectal cancer. Herein, we propose a simple, low-cost, and eco-friendly template-assisted filtration method for the scalable preparation of carbon nanotube-bridged TiCT MXene (MX@CNT) electrode arrays with a conductive network. Furthermore, we fabricate a homogeneous electrochemical (HEC) sensor for CEA detection by integrating a magnetic-bead-based alkaline phosphatase-linked immunoassay (MB-aElisa), which enables the in-situ generation of the electroactive substance 1-naphthol (1-NP).

Electrochemical detection of nitrofurazone using laser-engraved three-electrode graphene array.

Background: Nitrofurazone (NFZ) is a widely-used antimicrobial agent in aquaculture. The NFZ residue can be transmitted to humans through the food chain, and cause adverse health effects including carcinogenesis and teratogenesis. Until now, a number of modified electrodes have been developed for NFZ detection, however, there are some issues that need to be improved.

TiCT/laser-induced graphene-based micro-droplet electrochemical sensing platform for rapid and sensitive detection of benomyl.

The design and fabrication of high-performance electrode devices are highly important for the practical application of electrochemical sensors. In this study, flexible three-dimensional porous graphene electrode devices were first facilely fabricated using common laser ablation technique at room temperature. After then, hydrophilic two-dimensional MXene (TiCT) nanosheet was decorated on the surface of the laser-induced graphene (LIG), resulting in disposable TiCT/LIG electrode devices.

Machine Learning-Assisted Automatically Electrochemical Addressable Cytosensing Arrays for Anticancer Drug Screening.

The high-throughput and accurate screening of anticancer drugs is crucial to the preclinical assessment of candidate drugs and remains challenging. Herein, an automatically electrochemical addressable cytosensor (AEAC) for the efficient screening of anticancer drugs is reported. This sensor consists of sectionalized laser-induced graphene arrays decorated by the rhombohedral TiO and spherical Pt nanoparticles (LIG-TiO-Pt) with high electrocatalytic activity for HO and a homemade Ag/Pt electrode couple fixed onto the robot arm.

Co-based metal-organic frameworks synthesized from poly(ethylene terephthalate) waste plastics for rapid detection of -phenylenediamine.

The environmental issues and health problems of waste plastics have attracted remarkable attention. It is quite important to convert waste plastics into high value-added electrochemical materials. Herein, four kinds of Co-based metal-organic frameworks (CoMOFs) were synthesized from poly(ethylene terephthalate) plastic, and their electrochemical applications were examined.

Cobalt-based conjugated coordination polymers with tunable dimensions for electrochemical sensing of p-nitrophenol.

Using planar π-conjugated 2,5-diamino-1,4-benzenedithiol as organic ligand, Co-based conjugated coordination polymers (CoCCPs) with different morphology were prepared through controlling the injection rate of Co. When the injection rate decreases from 1.00 to 0.

Graphene/metal-organic framework nano-sandwiches derived N, P-codoped porous carbon nanosheets as robust material for electrochemical analysis.

Construction of novel two-dimensional porous carbon nanosheets with superior electrochemical activity is of great challenge. Here, graphene/ZIF-8 nano-sandwiches derived N, P-codoped porous carbon nanosheets (N, P-codoped PCN) was easily obtained by sequential room temperature self-assembly and high-temperature carbonization method. Relative to the widely used physically exfoliated graphene nanosheets (GN) and graphene/ZIF-8 derived N-doped porous carbon nanosheets (N-doped PCN), N, P-codoped PCN displayed larger active surface, faster electron transport ability and stronger physical adsorption ability, which can be ascribed to the dual doping effect of heteroatoms N and P.

Size-Dependent Electrochemistry of Oxygenated Ti C T MXenes.

2D MXenes are widely proved to be potential electrode materials, although the size effect on their electrochemistry is not fully understood. In this work, Ti C T nanoflakes are prepared through acidic etching of Ti AlC powders, followed by the intercalation treatment with tetrapropylammonium hydroxide. Such a method produces large-scale delaminated and oxygenated nanoflakes.

Development of Nafion/single-walled carbon nanotube integrated arrays for the rapid detection of salbutamol doping.

Salbutamol (SAL), a drug originally intended for the treatment of bronchial and pulmonary diseases, has repeatedly been used for doping in competitive sports. Herein, an integrated array (NFCNT array) that prepared by template-assisted scalable filtration using Nafion-coated single-walled carbon nanotube (SWCNT) is presented for the rapid field detection of SAL. Spectroscopic and microscopic measurements were used to confirm the introduction of Nafion onto the surface of the array and to analyze the resulting morphological changes.

Electrochemically functionalized graphene for highly sensitive detection of nitrofurazone.

Graphene nanosheets (GS) were prepared by ultrasonic exfoliation of bulk graphite in -methyl-2-pyrrolidone with the assistance of sodium pyrophosphate. The obtained GS suspension was modified on a glassy carbon electrode (GS/GCE), and then functionalized at different voltages ( 1.0, 1.

Metal Centers and Organic Ligands Determine Electrochemistry of Metal-Organic Frameworks.

The properties and applications of metal-organic frameworks (MOFs) can be tuned by their metal centers and organic ligands. To reveal experimentally and theoretically the influence of metal centers and ligands on electrochemical performance of MOFs, three MOFs with copper or zinc centers and organic ligands of 2-methylimidazole (2MI) or 1,3,5-benzenetricarboxylic acid (H BTC) are synthesized and characterized in this study. 2D and porous Cu-2MI exhibits a larger active area, faster electron transfer capability, and stronger adsorption capacity than bulk Cu-BTC and dodecahedron Zn-2MI.

Two-Dimensional Red Phosphorus Nanosheets: Morphology Tuning and Electrochemical Sensing of Aromatic Amines.

Synthesis of 2D materials with different morphologies is of significance to reveal their morphology-dependent properties and further explore their morphology-dependent applications. This work reports the synthesis of 2D red phosphorus nanosheets (RPNSs) with different thicknesses by means of a phosphorus-amine method together with regulated electrophilicity of the solution. With graphene as the support, the RPNSs produced in 0.

Simultaneous detection of 4-chlorophenol and 4-nitrophenol using a TiCT MXene based electrochemical sensor.

Developing a sensitive and rapid detection method for 4-chlorophenol (4-CP) and 4-nitrophenol (4-NP) is very important due to their high toxicity. In this work, bulk TiAlC powder was etched to TiCT for the first time through a hydrothermal reaction in NaF/HCl solution. After ultrasonication in -methylpyrrolidone (NMP), TiCT powder was successfully exfoliated into multilayered TiCT nanosheets ( TiCT MXene).

Monodispersed Ni active sites anchored on N-doped porous carbon nanosheets as high-efficiency electrocatalyst for hydrogen peroxide sensing.

Metal active species combined with N-doped porous carbon nanosheets usually own excellent electrochemical activity and sensing performance owing to its unique microstructure and composition. In this work, monodispersed Ni active sites anchored on N-doped porous carbon nanosheets (Ni@N-PCN) were facilely prepared via rational metal-organic frameworks (MOFs) route. Firstly, zeolitic imidazolate frameworks-8 (ZIF-8) was in situ grown on physically-exfoliated graphene nanosheets (GN) with homogeneous sandwich-like structure (ZIF-8@GN).

Polyvinylpyrrolidone-assisted solvent exfoliation of black phosphorus nanosheets and electrochemical sensing of p-nitrophenol.

Few-layer black phosphorus (BP) has been considered as a rising star of 2D materials, and however, the poor stability heavily limits its application in electrochemical sensing. In this work, a series of BP nanosheets (BPNS) are simply prepared through ultrasonic exfoliation of bulk BP with the assistance of polyvinylpyrrolidone (PVP) in different solvents, including isopropanol (IPA), ethanol (EtOH), N-methyl pyrrolidone (NMP) and dimethylformamide (DMF). It is found that the exfoliation efficiency in IPA and EtOH is much higher than that in DMF and NMP, and moreover, IPA is superior than EtOH.

Cu-BTC frameworks based electrochemical sensor for hazardous malachite green in aquaculture.

Malachite green (MG) has been widely used for controlling external fungi and parasites in the aquaculture. However, MG has been proven to be very hazardous, and the detection of MG in aquaculture environment is crucial for determining whether MG has been used within the allowed limit and for protecting the environment. Herein, a kind of copper based metal-organic frameworks (MOFs) was prepared using copper nitrate and 1,3,5-benzenetricarboxylic acid (HBTC) as raw materials.

Poly(sulfosalicylic acid)-functionalized gold nanoparticles for the detection of tetrabromobisphenol A at pM concentrations.

Developing a sensitive, simple and fast sensing system for 3,3',5,5'-tetrabromobisphenol A (TBBPA) is important because of its ubiquitousness and high toxicity. In this work, a gold nanoparticles (AuNPs) and poly(sulfosalicylic acid) (PSSA) composite film (AuNPs-PSSA) is fabricated in-situ on an electrode surface via cyclic voltammetry scanning. The characterization via scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray (EDX) analysis and Fourier transform infrared (FTIR) spectroscopy indicate that the PSSA film is homogeneously decorated with AuNPs, and a highly uniform and thin composite film is obtained.

Triethylamine-controlled Cu-BTC frameworks for electrochemical sensing fish freshness.

The simultaneous determination of xanthine (XA) and hypoxanthine (HXA) has been proved to be a feasible approach for the assessment of fish freshness. In this study, copper(II) nitrate and 1,3,5-benzenetricarboxylic acid (HBTC) were used as precursors to prepare various Cu-BTC frameworks with the addition of various amounts of triethylamine at room temperature. The characterization of X-ray diffraction, Fourier-transform infrared spectroscopy and Raman spectroscopy testified that the obtained materials are Cu-BTC frameworks.

Ball-Mill-Exfoliated Graphene: Tunable Electrochemistry and Phenol Sensing.

A simple wet ball-milling method for exfoliating pristine graphite to graphene nanosheets is proposed. The surfactant of cetyltrimethyl ammonium bromide is utilized to greatly improve the exfoliation efficiency of graphene nanosheets. Variation of the ball-milling time is an efficient way to control the size and thickness of graphene nanosheets, as well as the level of edge defects.

Strategy for Highly Sensitive Electrochemical Sensing: In Situ Coupling of a Metal-Organic Framework with Ball-Mill-Exfoliated Graphene.

A highly sensitive electrochemical sensing system is developed via in situ integration of Cu-based metal-organic frameworks (Cu-BTC, BTC = 1,3,5-benzenetricarboxylic acid) and high-conductivity ball-mill-exfoliated graphene (Cu-BTC@GS) by a simple method. The as-synthesized Cu-BTC@GS hybrids display remarkably enhanced electrochemical activity due to the synergistic effect resulting from the integration. Compared to those of the pristine GS, the introduction of Cu-BTC nanoparticles leads to significant improvement in the surface area and porosity, as revealed by the nitrogen adsorption-desorption analysis.

Electrochemical sensing performance of Eu-BTC and Er-BTC frameworks toward Sunset Yellow.

Two lanthanide metal-organic frameworks (Ln-MOFs) using 1,3,5-benzenetricarboxylic acid (HBTC) and Ln(III) nitrate hydrate (Ln = Eu, Er) as precursors have been prepared through a one-step solvothermal approach. The as-synthesized compounds were characterized by X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy, confirming that the targeted Ln-MOFs were successfully synthesised, with a straw-sheaf appearance. Their sensing properties were studied using cyclic voltammetry and electrochemical impedance spectroscopy, and the results showed that the prepared Ln-BTCs possessed larger electrochemical-response areas and stronger electron-transport capability, especially the Er-BTC.

Morphology-dependent electrochemical sensing performance of metal (Ni, Co, Zn)-organic frameworks.

To clarify the morphology effect of metal-organic frameworks (MOFs) on their electrochemistry as well as to explore their electrochemical applications, three MOFs with metal centers of nickel, cobalt, and zinc are synthesized. The used organic ligand is only 1,3,5-benzenetricarboxylic acid. Characterizations using Fourier Transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and electrochemical techniques reveal that these MOFs possess similar bonding properties, crystalline structures and phase purity, but various morphology and electrochemical activities, including their own redox behavior, electrochemical response toward redox probes and analytes in solutions.

Portable, Self-Powered, and Light-Addressable Photoelectrochemical Sensing Platforms Using pH Meter Readouts for High-Throughput Screening of Thrombin Inhibitor Drugs.

In this work, a self-powered, portable, and light-addressable photoelectrochemical sensor (P-LAPECS) is developed for efficient drug screening using a handheld pH meter readout. The sensor, which employs thrombin inhibitors as the drug model, is constructed by evenly immobilizing biotin-labeled and thrombin-cleavable peptides on eight separated sensing zones of a single gold film electrode. The incubation of each peptide sensing zone with thrombin leads to the reduction of binding sites for streptavidin-labeled fullerene (C) PEC bioprobes, which directly reflects the activity of thrombin by the variation of both photocurrent and photovoltage, and therefore allows the screening of thrombin inhibitors using either a single-channel electrochemical analyzer or a portable pH meter.

Reduced graphene oxide-ZnO nanocomposite based electrochemical sensor for sensitive and selective monitoring of 8-hydroxy-2'-deoxyguanosine.

Developing reliable and feasible electrochemical sensors for the detection of 8-hydroxy-2'-deoxyguanosine (8-OHdG) is important because the urinary level of 8-OHdG is related to cancer disease. Moreover, the co-existed uric acid (UA) as an interference severe affects the sensitive detection of 8-OHdG. Herein, sensitive monitoring of 8-OHdG was conducted using a nanocomposite of reduced graphene oxide (rGO) and ZnO nanoparticles (ZnO@rGO) as the sensing material.