Switchable-hydrophilicity solvent-liquid-liquid microextraction (SHS-LLME), as an efficient sample cleanup method, was combined with dispersive solid-phase microextraction (DSPME) for preconcentration of quercetin prior to its spectrophotometric determination. Optimum SHS-LLME were found as 1000 μL of N,N-dimethylcyclohexylamine as the extraction solvent and 750 μL of 10.0 M sodium hydroxide as the phase separation trigger. Optimum DSPME were sample pH at 6.0, 1000 μL of acetone as the eluent, 30.0 mL of sample, 12.5 mg of Fe₃O₄@XAD-16 as the adsorbent, 4.0 and 1.5 min as the adsorption and elution times, respectively. Calibration graphs with coefficient of determination (R²) higher than 0.9956, limits of detection (LOD) of 9.0–11.9 ng mL⁻¹ and limits of quantitation (LOQ) of 29.9–39.6 ng mL⁻¹ were obtained. Repeatability, expressed as percentage relative standard deviation (%RSD), was better than 3.2 and 8.9% for intra- and inter-day precision, respectively. The proposed SHS-LLME-DSPME-UV/Vis method was applied for the determination of quercetin in four food samples (i.e., apple, pepper, red and white onion) with percentage recoveries in the range of 92.1–107.4%. The proposed method is superior to others in terms of greenness, rapidness, simplicity, good repeatability and low capital cost.

可切换亲水性溶剂-液-液微萃取 (SHS-LLME) 作为一种有效的样品净化方法，与分散固相微萃取 (DSPME) 相结合，在分光光度法测定之前预浓缩槲皮素。发现最佳 SHS-LLME 为 1000 μL N,N-二甲基环己胺作为萃取溶剂，750 μL 10.0 M 氢氧化钠作为相分离触发剂。最佳 DSPME 是样品 pH 为 6.0，1000 μL 丙酮作为洗脱液，30.0 mL 样品，12.5 mg Fe ₃ O ₄ @XAD-16 作为吸附剂，吸附和洗脱时间分别为 4.0 和 1.5 分钟。具有确定系数的校准图 (R ²）高于0.9956，的9.0-11.9检测（LOD）的限制纳克毫升^-1和29.9-39.6每mL（LOQ）定量限^-1得到。以相对标准偏差百分比 (%RSD) 表示的重复性分别优于 3.2% 和 8.9% 的日内和日间精密度。建议的 SHS-LLME-DSPME-UV/Vis 方法用于测定四种食品样品（即苹果、胡椒、红洋葱和白洋葱）中的槲皮素，回收率范围为 92.1-107.4%。所提出的方法在绿色、快速、简单、良好的可重复性和低资本成本方面优于其他方法。