School of Environment, Henan Key Laboratory for Environmental Pollution Control, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, International Joint Laboratory on Key Techniques in Water Treatment, Henan Province, Henan Normal University, Xinxiang, Henan 453007, PR China.
School of Environment, Henan Key Laboratory for Environmental Pollution Control, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, International Joint Laboratory on Key Techniques in Water Treatment, Henan Province, Henan Normal University, Xinxiang, Henan 453007, PR China.
J Chromatogr A. 2020 May 10;1618:460876. doi: 10.1016/j.chroma.2020.460876. Epub 2020 Jan 13.
For this work, a novel air-assisted liquid-liquid microextraction based on solidification of floating deep eutectic solvent (AA-LLME-SFDES), coupled with a high performance liquid chromatography (HPLC) method was developed for the detection of benzophenone and salicylate ultraviolet filters in water samples. Three types of fatty acid-based hydrophobic deep eutectic solvents (DESs) with low viscosity, low-density, and melting point close to room temperature were prepared and employed as extraction solvents. This air-assisted liquid-liquid microextraction was carried out in a glass centrifuge tube. Subsequently, the glass tube was introduced into ice-water bath and held for 3 min, during which the upper DES phase was solidified. The water phase was easily extracted using a syringe equipped with a long needle, and later, the glass tube was removed from ice-water bath. The solidified DES phase was immediately melted at room temperature and used for HPLC analysis. The response surface methodology was employed to optimize some influencing parameters such as the volume of the extraction solvent, the pH value of sample solution, the number of extraction cycles, and the addition of salt. A quadratic model, namely a central composite design, was used to replace the conventional single factor analysis. It was found that under optimal conditions, the limits of determination and quantification were 0.045-0.54 µg L and 0.15-2.0 µg L, respectively. The relative standard deviations for inter-day (n = 5) and intra-day (n = 5) precision were ≤ 4.2%, whereas the enrichment factors for the ultraviolet filters were obtained from 41 to 50. Furthermore, this novel method was successfully employed for the detection of benzophenone and salicylate ultraviolet filters from real water samples. The recoveries ranged from 87.5% to 105.8%, whereas the RSDs were lower than 3.6%.
本文开发了一种基于固态分散的新型空气辅助液-液微萃取方法（AA-LLME-SFDES），结合高效液相色谱（HPLC）法，用于检测水样中的二苯甲酮和水杨酸酯类紫外滤光剂。制备了三种类型的基于脂肪酸的疏水性深共晶溶剂（DESs），它们具有低粘度、低密度和熔点接近室温的特点，并将其用作萃取溶剂。该空气辅助液-液微萃取在玻璃离心管中进行。随后，将玻璃管放入冰-水浴中并保持 3 分钟，在此期间，上层 DES 相被固化。用水相注射器和长针头很容易将水相萃取出来，然后将玻璃管从冰-水浴中取出。在室温下，固态 DES 相立即融化，用于 HPLC 分析。采用响应面法优化了一些影响参数，如萃取溶剂的体积、样品溶液的 pH 值、萃取循环的次数和盐的添加量。采用二次模型（即中心复合设计）代替传统的单因素分析。结果发现，在最佳条件下，该方法的检测限和定量限分别为 0.045-0.54μg/L 和 0.15-2.0μg/L。日内（n=5）和日间（n=5）精密度的相对标准偏差均≤4.2%，而紫外滤光剂的富集因子为 41-50。此外，该新方法成功用于实际水样中二苯甲酮和水杨酸酯类紫外滤光剂的检测。回收率范围为 87.5%-105.8%，相对标准偏差低于 3.6%。
