This work presents the integration between phase-separation by magnetic-stirring salt-induced high-temperature liquid-liquid extraction (PS-MSSI-HT-LLE) and batch injection analysis with amperometric detection (BIA-AD) as an alternative strategy for pre-concentration of analytes before hydrodynamic electroanalysis. To demonstrate the performance of this analytical system, the emerging contaminant levofloxacin was quantified in tap, aquarium and lake water at low concentration level. In the optimized conditions, BIA-AD enabled fast (160 h−1) and reproducible results (RSD<2 %) and the PS-MSSI-HT-LLE allowed the detection of levofloxacin concentration levels not detected by direct electroanalysis (70 and 80 nmol L−1) corresponding to 100-folds enrichment factors. The performance of proposed method was evaluated by addition-recovery test and was obtained satisfactory recovery values (between 70 and 96 %). Moreover, PS-MSSI-HT-LLE allows the pre-concentration of many samples simultaneously, which is advantageous over pre-concentration on working electrode surface (stripping methods).

中文翻译：

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液-液萃取结合批量进样分析用于低浓度左氧氟沙星的电分析

这项工作提出了磁搅拌盐诱导高温液-液萃取 (PS-MSSI-HT-LLE) 相分离与安培检测分批注射分析 (BIA-AD) 之间的集成，作为预- 水动力电分析前分析物的浓度。为了证明该分析系统的性能，在自来水、水族馆和湖水中以低浓度对新出现的污染物左氧氟沙星进行了定量。在优化条件下，BIA-AD 实现了快速 (160 h-1) 和可重现的结果 (RSD<2 %)，并且 PS-MSSI-HT-LLE 允许检测直接电解分析未检测到的左氧氟沙星浓度水平（70 和 80 nmol L-1) 对应于 100 倍富集因子。通过添加回收试验评估了所提出方法的性能，并获得了令人满意的回收率值（在 70% 和 96% 之间）。此外，PS-MSSI-HT-LLE 允许同时预浓缩许多样品，这优于在工作电极表面预浓缩（剥离方法）。