Abstract Quadrupole isotope dilution mass spectrometry (ID4MS) and switchable solvent based liquid phase microextraction (SS-LPME) were combined to determine 4‑n‑nonylphenol (NP) in municipal waste water samples at trace levels. In this method, SS-LPME served as a preconcentration technique to reach trace levels for NP, while ID4MS was used as a measurement technique to improve accuracy and precision of the proposed method. A response surface methodology was performed to investigate the key parameters of SS-LPME method. Analysis of variance (ANOVA) was employed to assess the main experimental parameters and their interactions each other. Three calibration blends and one waste water sample blend were prepared with NP and 4‑n‑nonylphenol-D8 (NP-D8) for the application of SS-LPME-ID4MS. All the system parameters were optimized to improve the accuracy and detection power. Recovery of the SS-LPME-ID4MS method for waste water spiked at 40 ng g−1 was calculated as 101.5 ± 0.4%. This result does not only establish good applicability of the method to waste water, but also confirms the high accuracy and precision at a low concentration.

中文翻译：

---

可切换溶剂液相微萃取-气相色谱-四极杆同位素稀释质谱法测定城市废水中的 4-n-壬基苯酚

摘要 四极杆同位素稀释质谱 (ID4MS) 和可切换溶剂型液相微萃取 (SS-LPME) 相结合，测定城市废水样品中痕量水平的 4-n-壬基苯酚 (NP)。在该方法中，SS-LPME 作为一种预浓缩技术以达到 NP 的痕量水平，而 ID4MS 作为一种测量技术来提高所提出方法的准确度和精密度。执行响应面方法来研究 SS-LPME 方法的关键参数。方差分析 (ANOVA) 用于评估主要实验参数及其相互之间的相互作用。使用 NP 和 4-n-壬基苯酚-D8 (NP-D8) 制备了三种校准混合物和一种废水样品混合物，用于 SS-LPME-ID4MS。对所有系统参数进行了优化，以提高准确性和检测能力。SS-LPME-ID4MS 方法对添加 40 ng g-1 的废水的回收率计算为 101.5 ± 0.4%。该结果不仅确立了该方法对废水的良好适用性，而且证实了低浓度下的高精度和精密度。