Abstract In the present study, an accurate and selective preconcentration/extraction method was developed for the determination of nickel at trace levels. Slotted quartz tube flame atomic absorption spectrometry (SQT-FAAS) combined with dispersive liquid-liquid microextraction (DLLME) was used to obtain a very low detection limit for nickel. A Schiff base ligand derived from the reaction of 5-bromosalicylaldehyde and o-phenylenediamine was used for the formation of a coordinate nickel complex. Under the determined experimental conditions, the detection and quantification limits of the DLLME-SQT-FAAS system were calculated as 4.9 and 16.4 ng/mL, respectively. Satisfactory analytical performance values of the SQT-FAAS, DLMME-FAAS and DLLME-SQT-FAAS methods were obtained and 1.8, 32.0, 66.4-fold enhancements in detection power were respectively obtained over the conventional FAAS system. The percent recovery ranges obtained for two different spike concentrations were 88.1–113.2% and 102.1–120.2% for coffee and chamomile tea samples, respectively.

中文翻译：

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使用席夫碱配体分散液液微萃取法预浓缩后，采用槽纹石英管火焰原子吸收光谱法测定洋甘菊茶和咖啡样品中的痕量镍

摘要 在本研究中，开发了一种准确且选择性的预浓缩/提取方法，用于测定痕量水平的镍。开槽石英管火焰原子吸收光谱法 (SQT-FAAS) 结合分散液液微萃取 (DLLME) 用于获得非常低的镍检测限。源自 5-溴水杨醛和邻苯二胺反应的席夫碱配体用于形成配位镍配合物。在确定的实验条件下，DLLME-SQT-FAAS 系统的检测限和定量限分别计算为 4.9 和 16.4 ng/mL。SQT-FAAS、DLMME-FAAS 和 DLLME-SQT-FAAS 方法的分析性能值令人满意，分别为 1.8、32.0、66。与传统的 FAAS 系统相比，检测能力分别提高了 4 倍。对于咖啡和洋甘菊茶样品，两种不同加标浓度获得的百分比回收率范围分别为 88.1-113.2% 和 102.1-120.2%。