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A machine learning‐based microwave spectrum detection method based on the nitrogen vacancy (NV) color centers in diamonds is proposed. The functional relationship between the fluorescence spectrum and standard microwave spectrum is established. The response matrix is calculated using the Tikhonov regularization technique, and an unknown microwave spectrum is reconstructed. Diamond particles with a size of only 5 × 5 μm2 are placed in the microfluidic structures. Consequently, the frequency detection range of the microwave spectrum is from 2.892 to 6.214 GHz with a resolution of 22 kHz. The proposed research opens new paths for microwave spectrum detection and imaging at the microscopic scale. [ABSTRACT FROM AUTHOR]

The article focuses on a study related to usage of Electrospray Ionization Mass Spectrometry (ESI-MS) for examination of proteins and ligands interactions. Topics discussed include attainment of accurate reaction kinetics through ESI-MS, determination of protein-ligand complexes binding affinity, utilization of lysozyme for interactions investigation, combination of mathematical methods for quantification of complexes and comparison of results for interactions with the fluorescence method.

The concentration of methylmercury (MMC) and total mercury (TMC) in marine fishes (five species) frequently consumed in the coastal areas of Zhejiang province, China, was determined. The method of high-performance liquid chromatography–atomic fluorescence spectrometry (HPLC-AFS) with the microwave-assisted extraction was used for the MMC determination. TMC was analysed by a direct mercury analyser. MMC and TMC concentrations in five fish species ranged from 53 to 158 µg kg−1 and 60 to 172 µg kg−1, respectively. The proportion of MMC levels in TMC was greater than 80%. The highest MMC and TMC levels were found in Hairtail. [ABSTRACT FROM AUTHOR]

Abstract: A new fluorescent probe, DN-SB, was synthesized. DN-SB was based on the naphthalimide derivatives and exhibited high selectivity and sensitivity for Cu2+ ions. As a Cu2+-amplified fluorescent probe, its fluorescence spectrum showed 4.5-fold enhancement in the intensity of the signal at 519nm on binding with the Cu2+. Based on the fluorescence titration spectra and job’s-plot, binding mode of DN-SB with Cu2+ was proposed. Fluorescence intensity was linear with concentration of Cu2+ cation in a range from 4μM to 7μM. DN-SB was also sensitive for copper ions. The detection limit was calculated to be 0.15μM which indicated DN-SB was sensitive to Cu2+. [Copyright &y& Elsevier]