Cattail spike-like Co(OH)[email protected]3O4 nanoporous arrays were successfully prepared on nickel foam by hydrothermal method and calcination treatment. The Co(OH)[email protected]3O4 nanoarrays, combining the advantages of the Co(OH)F and the Co3O4, exhibit ultrahigh structural stability and excellent electrochemical performance. The specific capacitance of Co(OH)[email protected]3O4 is 543F g−1 at the current density of 1A g−1 and could maintain 88.34 % specific capacitance after 5000 cycles at 10 A g−1. Moreover, a two-electrode system assembled by Co(OH)[email protected]3O4 and reduced graphene oxide exhibits a peak energy density of 30.155 Wh kg−1 at the power density of 800 W kg−1 and possesses an excellent cycling retention of 84.88 % after 5000 cycles at 10A g−1. These results indicate that the prepared Co(OH)[email protected]3O4 composite is a promising positive electrode material for supercapacitors. 

Cattail spike-like Co(OH)F@Co3O4 nanoarrays for high-performance supercapacitors

Plasmonic nanomaterials have been intensively explored for applications in biomedical detection and therapy for human sustainability. Herein, plasmonic gold nanoisland (NI) film (AuNIF) was fabricated onto a glass substrate by a facile seed-mediated growth approach. The structure of the tortuous gold NIs of the AuNIF was demonstrated by scanning electron microscopy and energy-dispersive X-ray spectroscopy. Based on the ultraviolet-visible spectrum, the AuNIF revealed plasmonic absorption with maximum intensity at 624 nm. With the change to the surface topography created by the NIs, the capture efficiency of Escherichia coli (E. coli) by the AuNIF was significantly increased compared to that of the glass substrate. The AuNIF was applied as a surface-enhanced Raman scattering (SERS) substrate to enhance the Raman signal of E. coli. Moreover, the plasmonic AuNIF exhibited a superior photothermal effect under irradiation with simulated AM1.5 sunlight. For photothermal therapy, the AuNIF also displayed outstanding efficiency in the photothermal killing of E. coli. Using a combination of SERS detection and photothermal therapy, the AuNIF could be a promising platform for bacterial theranostics.

Plasmonic Gold Nanoisland Film for Bacterial Theranostics.

Metal-organic frameworks: A promising option for the diagnosis and treatment of Alzheimer's disease.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder with a long latency in the "prodromal" stage, for which there are currently no effective treatments. It is generally accepted that accurate diagnosis and subsequent treatment in the early stages of AD may lead to better therapeutic outcomes. Detection of body fluid biomarkers is an effective strategy for early AD diagnosis. Among them, amyloid β(1–42) (Aβ42), as one of the most important biomarkers of AD, plays a key role in the progression of AD. Currently, electrochemical biosensors offer many advantages in monitoring Aβ42 because they are fast, portable, and capable of on-site analysis. This article provides an overview of the dynamics of Aβ42 levels in biological fluids as AD progresses, followed by a detailed description of the design and analytical performance of various electrochemical sensors. Finally, the challenges of electrochemical sensors for AD diagnosis are discussed, and prospects and trends are outlined. 

Recent advances in electrochemical biosensors for the detection of Aβ42, a biomarker for Alzheimer disease diagnosis

In this study, boron carbide powders consisting mainly of nano/micro fibers or polyhedral-equiaxed particles were synthesized via the sol–gel technique, and the influence of particle morphology on electrochemical performance of boron carbide electrodes was investigated. Thermal decomposition duration of the precursors played a determinant role in the final morphology of the synthesized boron carbide powders. The morphology of boron carbide powders successfully tuned from polyhedral-equiaxed (with ~3 µm average particle size) to nano/micro fibers by adjusting the thermal decomposition duration of precursors. The length and thickness of fibers were in the range of 30 to 200 µm and sub-micron to 5 µm, respectively. The electrochemical performance analysis of boron carbide powders has shown that the particle morphology has a considerable impact on the boron carbide electrodes electrochemical performance. It was found that the synergetic effects of polyhedral-equiaxed and nano/micro fiber morphologies exhibited the best electrochemical performance in supercapacitor devices, resulting in the power and energy density of 34.9 W/kg and 0.016 Wh/kg, respectively.

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Boron Carbide as an Electrode Material: Tailoring Particle Morphology to Control Capacitive Behaviour

The development of minimally invasive and easy-to-use sensor devices is of current interest for ultrasensitive detection and signal recognition of Alzheimer's disease (AD) biomarkers. Over the years, tremendous effort has been made on diagnostic platforms specifically targeting neurological markers for AD in order to replace the conventional, laborious, and invasive sampling-based approaches. However, the sophistication of analytical outcomes, marker inaccessibility, and material validity strongly limit the current strategies towards effectively predicting AD. Recently, with the promising progress in biosensor technology, the realization of a clinically applicable sensing platform has become a potential option to enable early diagnosis of AD and other neurodegenerative diseases. In this review, various types of biosensors, which include electrochemical, fluorescent, plasmonic, photoelectrochemical, and field-effect transistor (FET)-based sensor configurations, with better clinical applicability and analytical performance towards AD are highlighted. Moreover, the feasibility of these sensors to achieve point-of-care (POC) diagnosis is also discussed. Furthermore, by grafting nanoscale materials into biosensor architecture, the remarkable enhancement in durability, functionality, and analytical outcome of sensor devices is presented. Finally, future perspectives on further translational and commercialization pathways of clinically driven biosensor devices for AD are discussed and summarized.

/pdf/clinically-oriented-alzheimer-s-biosensors-expanding-the-2t788tifxk.pdf

Clinically oriented Alzheimer's biosensors: expanding the horizons towards point-of-care diagnostics and beyond

A cobalt oxide (Co3O4)-decorated silicon carbide (SiC) nano-tree array (denoted as Co3O4/SiC NTA) electrode is synthesized, and it is investigated for use in micro-supercapacitor applications. Firstly, the well-standing SiC nanowires (NWs) are prepared by nickel (Ni)-catalyzed chemical vapor deposition (CVD) method, and then the thin layer of Co3O4 and the hierarchical Co3O4 nano-flower-clusters are, respectively, fabricated on the side-walls and the top side of the SiC NWs via electrodeposition. The deposition of Co3O4 on the SiC NWs benefits the charge transfer at the electrode/aqueous electrolyte interface due to its extremely hydrophilic surface characteristic after Co3O4 decoration. Furthermore, the Co3O4/SiC NTA electrode provides a directional charge transport route along the length of SiC nanowires owing to their well-standing architecture. By using the Co3O4/SiC NTA electrode for micro-supercapacitor application, the areal capacitance obtained from cyclic voltammetry measurement reaches 845 mF cm-2 at a 10 mV s-1 scan rate. Finally, the capacitance durability is also evaluated by the cycling test of cyclic voltammetry at a high scan rate of 150 mV s-1 for 2000 cycles, exhibiting excellent stability.

Po Kang Yang

Papers

Clinically oriented Alzheimer's biosensors: expanding the horizons towards point-of-care diagnostics and beyond

Cobalt Oxide-Decorated Silicon Carbide Nano-Tree Array Electrode for Micro-Supercapacitor Application.