高效液相色谱法定量测定果蔬中甲醛含量

通过五氟苯肼与甲醛进行衍生，建立高效液相色谱法定量测定果蔬中甲醛含量的分析方法。样品在温度为60 ℃超声波条件下直接提取衍生30 min，离心纯化后高效液相色谱检测，外标法定量。优化的色谱条件为：XDB-C18色谱柱（4.6 mm×250 mm，5 μm），流动相：乙腈-水（70∶30，V/V），流速1.0 mL/min，柱温40 ℃，检测波长258 nm。结果表明，该方法的定量检测限可达到0.114 mg/kg，在0.114～57 mg/L范围内呈良好的线性关系，当甲醛添加量分别为1.14、8.55、17.10 mg/kg时，平均回收率为81.4%～101.8%，相对标准偏差为2.6%～5.0%（n=6）。该方法样品前处理简便、稳定性好、检测限低，适合果蔬中甲醛含量的快速检测。

Determination of Formaldehyde in Fruits and Vegetables by HPLC

A high performance liquid chromatography (HPLC) method was used to determine formaldehyde in fruits and vegetables by formaldehyde derivation with pentafluorophenylhydrazine (PFPH). Samples were extracted and derived at 70 ℃ with ultrasonicaction for 30 min. After completion of the reaction, centrifugation was carried out and the supernatant was purified and analyzed by HPLC. The quantitation was performed using the external standard method. The separation was performed on an XDB-C18 column (4.6 mm × 250 mm, 5 μm) in an isocratic elution mode using a mobile phase consisting of acetonitrile and water (70:30, V/V) at a flow rate of 1.0 mL/min. The column temperature was 40 ℃ and detection wavelength was 258 nm. The results showed that the limit of quantification (LOQ) of the presented method was 0.114 mg/kg, with a good linear relationship in the range of 0.114–57 mg/L. The average recovery rates at three spiked levels were 81.4%–101.8%, with relative standard derivation (RSD) of 2.6%–5.0% (n = 6). The method was simple, stable and suitable for the determination of formaldehyde in fruits and vegetables with a low limit of detection (LOD).