液相色谱-串联质谱法测定糙皮侧耳中9种植物生长调节剂的残留量

建立了液相色谱-串联质谱仪(Liquid Chromatography-Tandem Mass Spectrometry,LC-MS/MS)同时测定糙皮侧耳(Pleurotus ostreatus)中吲哚乙酸、吲哚丙酸、吲哚丁酸、赤霉素、2,4-二氯苯氧乙酸、6-苄基腺嘌呤、4-氯苯氧乙酸、6-糠氨基嘌呤和芸苔素内酯9种植物生长调节剂残留的定量分析方法,样品经含1%(v/v)乙酸的乙腈溶液提取,于分散固相萃取管(含混匀的150mg MgSO_4和50mg C_(18))净化后用LC-MS/MS检测。结果表明:9种植物生长调节剂的峰面积与其浓度呈良好线性关系,方法最低检出限为0.5~1.0μg/kg;回收率为80.3%~96.5%,相对标准偏差为0.88%~7.31%,该方法准确、可靠,可以同时满足糙皮侧耳中9种植物生长调节剂残留检测的需要。对市场上50份糙皮侧耳的测定结果为:吲哚乙酸检出6次(2.3~96.7μg/kg)、吲哚丙酸2次(21.3、87.8μg/kg)、吲哚丁酸5次(3.4~91.2μg/kg)。

Determination of Nine Plant Growth Regulator Residues in Pleurotus ostreatus Fruit Bodies Using LC-MS/MS

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed to simultaneously determine the residual levels of nine plant growth regulators (3-indole-acetic acid, indole-3-propionic acid, 3-indolebutyric acid, gibberellic acid, 2,4-dichlorophenoxyacetic acid, 6-benzylaminopurine, 4-chlorophenoxyacetic acid, kinetin and brassinolide) in Pleurotus ostreatus fruit bodies.Samples were first extracted with acetonitrile containing 1% (v/v) acetic acid, clarified by dispersive solid-phase extraction using a mixture of MgSO4 (150 mg) and C18(50 mg), and analyzed by LC-MS/MS.Standardization experiments revealed the methodology to be accurate and reliable, with calibration curves exhibiting good linearity over the concentration range 0.5-200 μg/L and detection limits of 0.5-1.0 μg/kg.Recovery rates ranged between 80.3% and 96.5% with Relative Standard Deviation values varying between 0.88% and 7.31%.Of 50 P.ostreatus fruit body samples obtained from supermarkets and farm product markets, 3-indole-acetic acid (2.3-96.7 μg/kg) was detected on six occasions, and indole-3-propionic acid (21.3 and 87.8 μg/kg) and 3-indolebutyric acid (3.4-91.2 μg/kg) each five times.