The Slight Adjustment in the Weight of Sulfur Sheets to Synthesize β-NiS Nanobelts for Maintaining Detection of Lower Concentrations of Glucose through a Long-Term Storage Test

The β-nickel sulfide (β-NiS) nanobelts were fabricated by electrodepositing a nickel nanosheet film on Indium tin oxide (ITO)-coated glass substrates and sulfuring the nickel film on ITO-coated glass substrates. The sulfurization method can be used to form nanobelts without a template. A small glass tube was used to anneal the sulfur sheet with a nickel nanosheet film. After applying vacuum to the tube, the specimen was annealed at 500 °C. By adjusting the weight of the sulfur sheet in a small glass tube, a nanobelt structure can be formed on the film for 4 h. The β-NiS nanobelt film had a sulfide and nickel molar ratio that was nearly 0.7 (S/Ni). After five years of a long-term storage test, the β-NiS nanobelt films were able to measure the glucose in a solution with the value of sensitivity of 8.67 µA cm-2 µM-1. The β-NiS nanobelt film also detected glucose with a limit of low detection (LOD) of around 0.173 µM. The estimation of reproducibility was over 98%. Therefore, the β-NiS nanobelt film has a significant ability to detect low concentrations of glucose in a solution.

Shpol'skii spectroscopy of metabolites of polycyclic aromatic hydrocarbons in primary alcohols at 77 K and 4.2 K

We present for the first time experimental evidence on the line-narrowing effect caused by primary alcohols on the spectral features of metabolites of polycyclic aromatic hydrocarbons at 77 K and 4.2 K. The investigated metabolites include 1-hydroxypyrene, 2-hydroxyfluorene, 9-hydroxyphenanthrene, 3-hydroxybenzo[a]pyrene, 4-hydroxybenzo[a]pyrene, 5-hydroxybenzo[a]pyrene, B[a]P-trans-7,8-dihydrodiol (±), B[a]P-trans-9,10-dihydrodiol (±), B[a]P-r-7,t-8-dihydrodiol-c-9,10-epoxide (±) and B[a]P-r-7,t-8-dihydrodiol-t-9,10-epoxide(±). The narrowest spectra and highest fluorescence enhancements were observed by matching the length of the alcohol to the length of the n-alkane that best fits the molecular dimensions of the parent polycyclic aromatic hydrocarbons. The analytical figures of merit show potential for the qualitative and quantitative analysis of PAH metabolites via Shpol'skii Spectroscopy.

Nanomaterials for sample pretreatment prior to capillary electrophoretic analysis

Nanomaterials are, in analytical science, used for a broad range of purposes, covering the area of sample pretreatment as well as separation, detection and identification of target molecules.

High Performance Non-enzymatic Glucose Sensor Based on One-Step Electrodeposited Nickel Sulfide

Nanostructured NiS thin film was prepared by a one-step electrodeposition method and the structural, morphological characteristics of the as-prepared films were analyzed by X-ray diffractometry (XRD), field emission scanning electron microscopy (FESEM) and energy dispersive X-ray analysis (EDAX). The electrocatalytic activity of NiS thin film towards glucose oxidation was investigated by fabricating a non-enzymatic glucose sensor and the sensor performance was studied by cyclic voltammetry (CV) and amperometry. The fabricated sensor showed excellent sensitivity and low detection limit with values of 7.43 μA μM(-1)  cm(-2) and 0.32 μM, respectively, and a response time of <8 s.

Electrodeposited spinel NiCo2O4 nanosheet arrays for glucose sensing application

Non-enzymatic glucose sensing properties of NiCo₂O₄ nanosheets show linear response with respect to the change in glucose concentration varying from 5 to 65 μM and exhibit the sensitivity value of 6.69 μA μM⁻¹ cm⁻² with a LOD value of 0.38 μM.