Abstract Reduction of matrix effect seems to be a great challenge for the development of a practical method in bioanalysis. In this regard, a simple and efficient DLLME procedure along with a back-extraction step (DLLME-BE) was developed for the preconcentration of four common non-steroidal anti-inflammatory drugs (NSAIDs) in various biological fluid samples. Briefly, the analytes of interest were initially transferred into the extraction solvent followed by the back-extraction into an immiscible basic methanol (as an acceptor phase) for further preconcentration and clean-up. The main purpose of the work is reducing the matrix effect and sensitive determination of target molecules in the complex matrices. Following on, the separation and determination of the analytes were carried out using GC–MS (in-port derivatization) and HPLC-DAD instrument. The influential parameters affecting the DLLME-BE method were evaluated in detail and the best extraction conditions were established. Under the optimum conditions, low method detection limits in the range of 0.1–1.0 and 0.1–6.0 µg L −1 were obtained for GC–MS and HPLC-DAD analysis, respectively. Additionally, fair intra-day precisions of 2.7–14.5 and 2.8–7.8% as well as inter-day precisions of 3.9–14.5 and 3.5–8.1% were achieved for the GC–MS and HPLC-DAD analysis, respectively. Finally, the method was successfully applied for the determination of four common NSAIDs in different biological fluid samples.

中文翻译：

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一种基于分散液-液微萃取结合反萃取的高效样品制备方法，用于酸性药物的痕量测定

摘要 降低基质效应似乎是开发实用的生物分析方法的一大挑战。在这方面，开发了一种简单有效的 DLLME 程序以及反萃取步骤 (DLLME-BE)，用于在各种生物体液样品中预浓缩四种常见的非甾体抗炎药 (NSAID)。简而言之，首先将目标分析物转移到萃取溶剂中，然后反萃取到不混溶的碱性甲醇（作为受体相）中，以进行进一步的预浓缩和净化。该工作的主要目的是降低复杂基质中目标分子的基质效应和灵敏测定。随后，使用 GC-MS（端口内衍生化）和 HPLC-DAD 仪器对分析物进行分离和测定。详细评估了影响DLLME-BE方法的影响参数，并建立了最佳提取条件。在最佳条件下，GC-MS 和 HPLC-DAD 分析分别获得了 0.1–1.0 和 0.1–6.0 µg L -1 范围内的低方法检测限。此外，GC-MS 和 HPLC-DAD 分析分别实现了 2.7-14.5 和 2.8-7.8% 的公平日内精密度以及 3.9-14.5 和 3.5-8.1% 的日间精密度。最后，该方法成功应用于不同生物体液样品中四种常见NSAIDs的测定。分别获得了 0 µg L -1 用于 GC-MS 和 HPLC-DAD 分析。此外，GC-MS 和 HPLC-DAD 分析分别实现了 2.7-14.5 和 2.8-7.8% 的公平日内精密度以及 3.9-14.5 和 3.5-8.1% 的日间精密度。最后，该方法成功应用于不同生物体液样品中四种常见NSAIDs的测定。分别获得了 0 µg L -1 用于 GC-MS 和 HPLC-DAD 分析。此外，GC-MS 和 HPLC-DAD 分析分别实现了 2.7-14.5 和 2.8-7.8% 的公平日内精密度以及 3.9-14.5 和 3.5-8.1% 的日间精密度。最后，该方法成功应用于不同生物体液样品中四种常见NSAIDs的测定。