盐析辅助均相液液萃取-高效液相色谱法测定蔬菜水果中对苯基苯酚残留

Determination of p-Phenylphenol Residues in Vegetables and Fruits Based on Salting-out Homogeneous Liquid-liquid Extraction and High Performance Liquid Chromatography

摘要:

建立了盐析辅助均相液液萃取结合高效液相色谱法测定蔬菜水果中对苯基苯酚残留的检测方法。试样经乙腈提取，用氯化钠盐析分层，以五氟苯基柱为色谱分离柱，甲醇-水为流动相梯度洗脱，二极管阵列/荧光双检测器，外标法定量。对提取溶剂、提取盐体系、净化、浓缩方法和稳定性等前处理的关键因素都进行了优化，并考察了不同色谱柱和流动相条件对分离效果的影响。结果表明，对苯基苯酚在0.05~100.00 µg/mL（二极管阵列检测器）和0.01~5.00 µg/mL（荧光检测器）范围内线性关系良好，相关系数（R2）均大于0.999，紫外和荧光条件下检出限分别为0.03 mg/kg和0.01 mg/kg，定量限分别为0.10 mg/kg和0.02 mg/kg。在3个空白添加浓度水平（LOQ、2LOQ和10LOQ），平均回收率分别为82.28%~110.7%和85.83%~109.8%，相对标准偏差（RSD）分别为2.60%~5.72%和2.66%~5.26%。该方法简便快捷、准确性和重现性较好，二极管阵列/荧光双串联检测可相互定性，特异性较好，适用于蔬菜水果中对苯基苯酚残留的测定。

Abstract:

An analytical method was established to detect p-phenylphenol residues in vegetables and fruits by salting-out homogeneous liquid–liquid extraction (SHLLE) and high performance liquid chromatography (HPLC). Samples were extracted with acetonitrile and separated from sample solutions by salting out with sodium chloride. Separation was performed on a reversed phase C18-PFP column using methanol-water as the mobile phase for gradient elution, and the analyte was detected using a diode array/fluorescence dual detector and quantified by an external standard method. Key pre-treatment factors such as extraction solvent, extraction salt system, purification, concentration method and stability, and the influence of different chromatographic columns and mobile phase conditions on the separation effect were investigated and optimized. The results showed a strong linear relationship for p-phenylphenol between 0.05 and 100.00 µg/mL (diode array detector) and 0.01 and 5.00 µg/mL (fluorescence detector), with correlation coefficients (R2) all greater than 0.999. Limits of detection (LOD) of 0.03 mg/kg and 0.01 mg/kg were obtained for the diode array detector under ultraviolet and fluorescent conditions, respectively, with the limits of quantification (LOQ) reaching 0.10 mg/kg and 0.02 mg/kg. Average recoveries of 82.28%~110.7% and 85.83%~109.8% with relative standard deviations (RSD) of 2.60%~5.72% and 2.66%~5.26% were obtained under the three blank concentrations (LOQ, 2LOQ, and 10LOQ), respectively. This method is simple and fast, with good accuracy and reproducibility. Diode array/fluorescence dual detection is mutually qualitative, has good specificity, and is suitable for the determination of p-phenylphenol residues in vegetables and fruits.