A sustainable approach utilizing a low-temperature molten salt strategy is employed in this study to fabricate homogeneous and dense NiFe nitrate hydroxide needle-like arrays on a NiFe foam substrate. The electrode also achieves an ultra-low voltage of 1.77 V at 100 mA cm and maintains stability for more than 120 h at a current density of 100 mA cm, showing excellent overall water splitting (OWS) performance and stability.
View Article and Find Full Text PDFConventional plate electrodes were commonly used in electrochemical flow injection analysis and only part of molecules diffused to the plane of electrodes could be detected, which would limit the performance of electrochemical detection. In this study, a low-cost native stainless steel wire mesh (SSWM) electrode was integrated into a 3D-printed device for electrochemical flow injection analysis with a pass-through mode, which is different compared with previous flow-through mode. This strategy was applied for sensitive analysis of hydrogen peroxide (HO) released from cells.
View Article and Find Full Text PDFRecently, production of hydrogen (H) through the urea oxidation reaction (UOR) and hydrogen evolution reaction (HER) has acquired great attention because it is more environmentally friendly and energy-saving. Herein, an approach of water activation was developed for growth of NiMo LDH nanosheet arrays on NiMo foam without using any binder or pressurizing or heating steps. The obtained NiMo foam electrodes showed exceptional catalytic activity and durability for both the UOR and HER.
View Article and Find Full Text PDFAlthough electrochemical detection based on molecular imprinting polymers (MIP) could dramatically improve the selectivity, the procedure is time-consuming because of the essential incubation step. In addition, current MIP electrochemical detections were not suitable for analysis of microliter-level sample solutions, limiting their applications for real samples. This investigation aims at applying vibration to enhance efficiency of MIP electrochemical detection of 20 μL sample solutions.
View Article and Find Full Text PDFIn this paper, a facile and ultrafast two-step dipping process was developed to form an electrocatalyst on a NiMo foam substrate without consuming extra energy. The obtained electrode showed a porous coral-like structure decorated with nanosheets and exhibited excellent overall water splitting properties in alkaline solution. This study provides a feasible strategy for developing an environmentally friendly and energy-efficient non-noble metal electrode for hydrogen production from water splitting.
View Article and Find Full Text PDFCurrently, the fabrication of low cost and high efficiency electrocatalysts is a hotspot in the study of water splitting. Herein, plasma spray (PS) was used to induce a microcosmic explosion () on Ni mesh to modify the nanoscale Ni for the preparation of -PS-NM electrodes with excellent hydrogen evolution. We also demonstrated that oxygen evolution could be significantly enhanced after the -PS-NM electrodes were doped with Fe.
View Article and Find Full Text PDFAlthough electrochemical detection of microliters-level solutions is attractive for analysis of low-amount biological samples, its performance could be weakened by limited mass transfer due to low Reynolds number and laminar flow. Herein we designed a 3D-printed electroanalytical device to apply vibration for improvement of mass transfer during electrochemical detection. In our approach, the droplet-size sample solution containing Indole-3-acetic acid (IAA, as a model) was directly applied on the effective surface of a disposable working electrode.
View Article and Find Full Text PDFNiFe layered double hydroxide (NiFe LDH) is a promising material with multiple functions. In this communication, a novel method is used to prepare NiFe LDH. This synthesis method is achieved galvanic-cell corrosion between nickel and iron substrates in aqueous solutions containing a halogen group anion (, Cl) at ambient temperature.
View Article and Find Full Text PDFA top-down strategy using acid etching followed by water soaking is utilized to synthesize autologous NiFe LDH nanosheets on NiFe foam without other metal ions, oxidizing agents or heating steps. The NiFe foam serves as both the metal source and substrate, and the obtained nanosheets are firmly anchored on the foam. The obtained ultrathin nanosheet arrays could greatly increase the electrocatalytic active sites.
View Article and Find Full Text PDFBecause of the pivotal point of Marchantia polymorpha (M. polymorpha) in plant evolution, its auxin (mainly indole-3-acetic acid, IAA) levels could provide useful evidence for the study of the evolution of IAA. However, M.
View Article and Find Full Text PDFDesigning earth-abundant electrocatalysts that are highly active, low-cost, and stable for the oxygen evolution reaction (OER) is crucial for electrochemical water splitting. However, in conventional electrode fabrication strategies, NiFe layered double hydroxide (NiFe LDH) catalysts are usually coated onto substrates as external components, which suffers from poor conductivity, easily detaches from the substrate, and hinders their long-term utilization. Herein, the surface-reconstruction strategy is used to synthesize in situ autologous NiFe LDH to increase the surficial active sites numbers.
View Article and Find Full Text PDFInspired by electronic transistors, electric field gating has been adopted to manipulate ionic currents of smart nanofluidic devices. Here, we report a PNP nanofluidic bipolar junction transistor (nBJT) consisting of one polyaniline (PANI) layer sandwiched between two polyethylene terephthalate (PET) nanoporous membranes. The PNP nBJT exhibits three different responses of currents (quasi-linear, rectification, and sigmoid) due to the counterbalance between surface charge distribution and base voltage applied in the nanofluidic channels; thus, they can be switched by base voltage.
View Article and Find Full Text PDFThis paper aims to use low-cost stainless steel wire mesh (SSWM) as uniform templates to prepare disposable three-dimensional (3D) carbon electrodes to improve their analytical performance. Native SSWM electrodes were prepared with lamination and then coated with carbon cement for bulk preparation of disposable 3D carbon electrodes with drop-casting. The electrodes were then coupled in paper-based analytical devices.
View Article and Find Full Text PDFBackground: Horseshoe kidney (HSK) is a common congenital defect of the urinary system. The most common complications are urinary tract infection, urinary stones, and hydronephrosis. HSK can be combined with glomerular diseases, but the diagnosis rate of renal biopsy is low due to structural abnormalities.
View Article and Find Full Text PDFChildren's shoes are potential sources of toxic heavy metals, especially for younger children. Electrochemical detection could be applied for effective stripping analysis of heavy metals (such as Cd and Pb). However, the substrates of working electrodes are still limited and it is not well known which property is critical.
View Article and Find Full Text PDFIn this paper, low-cost stainless steel sheets with excellent electric conductivity were utilized as the robust substrate for fabrication of disposable working electrodes. The stainless steel electrodes were modified with carbon cement and then coupled in paper-based analytical devices for analysis of heavy metals (cadmium and lead) in toys or indole-3-acetic acid (IAA) in plants, respectively. For stripping analysis of cadmium and lead, the dilution ratio of the carbon cement, the pH value of the buffer solution, the pre-deposition potential and time, and the bismuth concentration were optimized with the detection limits reaching 1 μg•L.
View Article and Find Full Text PDFRatiometric electrochemiluminescence (ECL) assays have been widely applied in biosensing because of eliminated outside interferences and improved reliability in detection. In order to construct ratiometric ECL biosensors with high sensitivity and reliability, it is critical to find two signal emitters with suitable applied potentials or emission wavelengths. This review aims to discuss recent advances and trends of ratiometric ECL biosensors in terms of ECL materials and corresponding ratiometric sensing approaches.
View Article and Find Full Text PDFIn this study, we proposed a dual-wavelength electrochemiluminescence resonance energy transfer (ECL-RET) ratiometric sensor combined with duplex-specific nuclease (DSN)-assisted target recycling amplification to detect microRNAs (miRNAs). Due to the perfect overlapping of spectra, the gold-nanoparticle-luminol-layered-double-hydroxides (Au NP-luminol-LDH) nanocomposite and gold nanoclusters (Au NCs) exhibited excellent ECL-RET effect with high efficiency. The Au NP-luminol-LDH donor exhibits a strong and stable ECL emission at the wavelength peak of 440 nm, while the Au NC acceptor has an emission peak at 620 nm.
View Article and Find Full Text PDFIn this study, we have developed a programmable electrochemiluminescence (ECL) system based on multi-segmented CdS-Au nanorod arrays with a sequential and highly tunable structure. The nanorod arrays were synthesized by an electrodeposition method using anodic aluminum oxide (AAO) as the template in which the Au and CdS segments were alternately electrodeposited. Compared to pure CdS nanorod arrays, multi-segmented CdS-Au nanorod arrays have showed a better ECL performance, which can be attributed to two factors: the favorable electron transfer and the surface plasma resonance (SPR) effect of the Au segment.
View Article and Find Full Text PDFSichuan Da Xue Xue Bao Yi Xue Ban
November 2017
Objective: To determine the expression level of long non-coding RNA (lncRNA) imprinted maternallyexpressed transcript () in colorectal cancer tissues and its effect on proliferation of colorectal cancer SW620 cells.
Methods: Real-time quantitative PCR (qRT-PCR) was applied to detect the expression of in 20 paired tumor tissues and adjacent normal tissues,and in normal NCM460 cells and colorectal cancer SW480,HCT116 and SW620 cells. The specific small interfering RNA for (si- group) or negative control sequence (si-NC group) were transfected into SW620 cells.
ACS Appl Mater Interfaces
September 2017
In this study, we proposed a nanopore-based electrochemiluminescence (ECL) sensor combined with duplex-specific nuclease (DSN)-assisted target recycling amplification to detect microRNAs. Because of the synergetic effect of electrostatic repulsion and volume exclusion of gold nanoparticle-labeled DNA capture (DNA-Au NPs) to the negatively charged luminol anion probe, the DNA-Au NP-modified anodized aluminum oxide (AAO) nanopore electrode exhibited high ECL decline in comparison with the bare AAO electrode. Upon the introduction of DSN and target microRNA, the specific DNA-RNA binding and enzyme cleaving could trigger the detachment of capture DNA from the membrane surface, resulting in uncapping of AAO and an increased ECL signal.
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