A novel Co ₉ S ₈ nanocage was fabricated via a metalorganic frameworks engaged strategy. The morphology and structure of the resulting Co ₉ S ₈ nanocage were carefully confirmed by scanning electron microscopy, powder X-ray diffraction, transmission electron microscope, and X-ray photoelectron spectroscopy. Then the as-synthesized Co ₉ S ₈ nanocage material was immobilized on a glassy carbon electrode (GCE) and served as an efficient sensing platform for determination of luteolin. Under optimized conditions, the prepared Co ₉ S ₈ /GCE shows significant electrocatalytic activity toward the oxidation of luteolin. By comparison with GCE and CoS/GCE, the proposed Co ₉ S ₈ /GCE results in great improvement in the electrochemical response of luteolin. Meanwhile, the Co ₉ S ₈ based-sensor presents an excellent linear relationship with the concentration of luteolin ranging from 0.01 to 20 μ M. Then, the limit of detection based on S/N = 3 was estimated to be 0.8 nM. In addition, the Co ₉ S ₈ /GCE displays good repeatability, reproducibility, and selectivity. Finally, the simplicity and low cost of this sensor makes it possible to determination luteolin in actual sample with good accuracy and precision.

In this study, three-dimensional porous MXene/carbon nanofiber (CNF) nanocomposites were prepared by assembling environmentally friendly and inexpensive bacterial cellulose (BC) gel sheets as a carbon source with novel two-dimensional MXenes nanoplate clusters and pyrolyzing the composite. The structure, morphology, and electrochemical properties of MXene/CNF was characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and electrochemical techniques. The experimental results revealed that the MXene/CNF nanocomposites had excellent electrical conductivity, large specific surface area, abundant active sites, and excellent electrochemical properties. The sensitive electrochemical determination of chloramphenicol (CAP) was achieved by constructing an electrochemical sensor using the MXene/CNF composite. The response current values of the MXene/CNF sensor exhibited a good linear response with CAP concentration ranging from 0.03-25μM, with a low detection limit of 9 nM. In addition, the sensor demonstrated good repeatability and reproducibility with relative standard deviations of 2.94 and 3.29%, respectively. Remarkably, the developed sensor was successfully used for the real-time detection of CAP in milk and jasmine tea beverage and satisfactory rates were obtained.

Background: Cross-linked porous carbon nanofibers (CNF) was successfully prepared by electrospinning and high-temperature carbonization. Polyacrylonitrile (PAN) as the carbon source and Genipin as the cross-linking agent were used to prepare Cross-linked porous carbon nanofibers (CNF). Method and Material: The field emission Scanning Electron Microscopy (SEM), Transmission Electron Microscope (TEM), Automatic Specific Surface and Porosity Analyzer Brunner Emmet Teller (BET), X-ray Diffraction (XRD), A laser confocal microspectroscope (Raman, XploRA PLUS, Horiba) were used to characterize materials. The CNF suspension was dropped on the surface of the bare glassy carbon electrode by the drip coating method to obtain a CNF modified electrode. Cyclic voltammetry was used to study the electrochemiluminescence behavior of difenidol hydrochloride on CNF modified glassy carbon electrode (Glassy Carbon Electrode, GCE). Results and Discussion: Herein, we synthesised a kind of Crosslinked Carbon Nanofibers and designed a novel ECL biosensor, Under the optimal conditions, the concentration of difenidol hydrochloride has a linear relationship with the peak current in the range of 8.0×10-8 to 1.0×10-4mol/L, the correlation coefficient is R2=0.997, with a low detection limit (1.2×10- 8 mol/L). Difenidol hydrochloride in difenidol hydrochloride tablets was tested, and the recovery rate of sample addition was 83.17%-92.17%, and the RSD was <5.0%. The designed platform exhibited excellent analytical performance towards difenidol hydrochloride determination.