A new fluorescent probe P based on rhodamine for Cu²⁺ was synthesized and characterized. The new probe P showed high selectivity to Cu²⁺ over other tested metal ions. With optimal conditions, the proposed probe P worked in a wide linear range of 1.0 × 10⁻⁶–1.0 × 10⁻⁵ M with a detection limit of 3.3 × 10⁻⁷ M Cu²⁺ in ethanol-water solution (9:1, v:v, 20 mM HEPES, pH 7.0). Furthermore, it has been used for imaging of Cu²⁺ in living cells with satisfying results.

A rapid and sensitive ionic liquid (IL) based headspace gas chromatography-mass spectrometry (HS-GC-MS) method was developed for analyzing volatile components in leaf, pericarp, and seed of Clausena lansium from different areas in Hainan Province, China. HS efficiencies were carefully investigated by using three ILs and water as matrix media. Extraction parameters, including equilibrium temperature, equilibrium time, and stirring rate had been evaluated and optimized by using an orthogonal design with OA₉(3³) table. Under the optimized condition of IL-based HS-GC-MS, only 100 mg of sample and 2 mL of [Bmim][BF₄] were needed to comprehensively and accurately analyze the volatile components in Clausena lansium. By utilizing a cluster analysis, six clusters were obtained for ninety components. This method was simpler, more rapid, and more sensitive when compared with previously reported methods for analyzing and identifying volatile components in Clausena lansium. The results may provide a theoretical basis for further exploitation of Clausena lansium.

A novel, simple and rapid method, termed dispersive liquid–liquid microextraction with solidification of floating organic drop coupled to high performance liquid chromatography, was developed for analysis of three phenolic oestrogens including diethylstilbestrol, dienestrol and hexestrol in human urine and water samples. The parameters of dispersive liquid–liquid microextraction with solidification of floating organic drop procedure including sample pH, type and volume of disperser solvent, and type and volume of extraction solvent were optimised. High performance liquid chromatography was applied for the phenolic oestrogens’ analysis. Under the optimum extraction and detection conditions, excellent analytical performances were attained. Good linear relationships (r ≥ 0.998) between peak area and concentration for diethylstilbestrol and dienestrol were optimised from 0.1 to 20 µg/mL, for hexestrol from 2 to 50 µg/mL. Method detection limits of 28.6–666.7 ng/mL were achieved. Satisfactory relative recoveries ranging from 72% to 122% were determined for urine, lake and tap water samples, with relative standard deviations (RSDs, n = 6) of 1.5–9.8%. The developed dispersive liquid–liquid microextraction with solidification of floating organic drop-high performance liquid chromatography method has a great potential in routine residual analysis of trace phenolic oestrogens in biological and water samples.