Yang Deng-Kai, Ding Wang-Hsien
Department of Chemistry, National Central University, Chung-Li 32054, Taiwan.
J Chromatogr A. 2005 Sep 23;1088(1-2):200-4. doi: 10.1016/j.chroma.2004.11.063.
This study describes a simple and sensitive method for determining the alkylphenolic compounds, 4-tert-octylphenol (4-t-OP), 4-nonylphenol isomers (4-NPs), and their monoethoxylates (4-t-OP1EO and 4-NP1EOs), in fresh fruits and vegetables. The method involves extracting a sample by a modified Nielson-Kryger steam distillation extraction using n-hexane for 1 h. The alkylphenolic compounds were identified and quantitated by gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode. Various pH values and amounts of NaCl added to the sample solution were evaluated as extraction conditions. The quantitation limit of this method was less than 0.2 ng/g in 10 g (fresh weight) of sample. Recovery of alkylphenolic compounds in spiked samples exceeded 64% while R.S.D. ranged from 1.0 to 9.8%. Alkylphenolic residues were detected in fresh fruits and vegetables at concentrations of 4-NPs and 4-t-OP from n.d. to 16 ng/g and from n.d. to 4.8 ng/g (fresh weight), respectively. NP1EO and OP1EO were always below the quantitation limit.
本研究描述了一种简单且灵敏的方法，用于测定新鲜水果和蔬菜中的烷基酚类化合物，即4-叔辛基苯酚（4-t-OP）、4-壬基酚异构体（4-NPs）及其单乙氧基化物（4-t-OP1EO和4-NP1EOs）。该方法包括使用正己烷通过改良的尼尔森-克里格蒸汽蒸馏萃取法对样品进行1小时的萃取。通过气相色谱-质谱联用仪（GC-MS）在选择离子监测（SIM）模式下对烷基酚类化合物进行鉴定和定量。评估了添加到样品溶液中的各种pH值和NaCl量作为萃取条件。该方法在10克（鲜重）样品中的定量限小于0.2纳克/克。加标样品中烷基酚类化合物的回收率超过64%，相对标准偏差（R.S.D.）范围为1.0%至9.8%。在新鲜水果和蔬菜中检测到的烷基酚残留量，4-NPs和4-t-OP的浓度分别为未检出至16纳克/克和未检出至4.8纳克/克（鲜重）。NP1EO和OP1EO始终低于定量限。
