邢麗杰等
摘 要:該文建立了超高效液相色譜-串聯(lián)質(zhì)譜法(UPLC-MS/MS)同時(shí)測(cè)定葡萄中4種植物生長(zhǎng)調(diào)節(jié)劑的方法。樣品經(jīng)乙腈提取,WAX小柱凈化,采用BEH C18色譜柱分離,以乙腈和水為流動(dòng)相進(jìn)行梯度洗脫。采用電噴霧離子化,負(fù)離子分段掃描和多反應(yīng)監(jiān)測(cè)模式(MRM)檢測(cè),外標(biāo)法定量。結(jié)果表明:赤霉素、對(duì)氯苯氧乙酸、氯吡脲、2,4-二氯苯氧乙酸在1~200ng/mL范圍內(nèi)線性關(guān)系良好,相關(guān)系數(shù)均大于0.990;4種植物生長(zhǎng)調(diào)節(jié)劑的方法檢出限均為0.2μg/kg,方法定量限為0.5μg/kg,樣品添加回收試驗(yàn)的平均回收率為74.8%~101.5%,相對(duì)標(biāo)準(zhǔn)偏差為3.3%~8.6%(n=7)。該方法簡(jiǎn)單、靈敏度高、分析時(shí)間短,適用于葡萄中4植物生長(zhǎng)調(diào)節(jié)劑的測(cè)定。
關(guān)鍵詞:超高效液相色譜-串聯(lián)質(zhì)譜;植物生長(zhǎng)調(diào)節(jié)劑;葡萄
中圖分類號(hào) S66 文獻(xiàn)標(biāo)識(shí)碼 A 文章編號(hào) 1007-7731(2015)10-33-03
Abstract:A method was established for determining 4 plant growth regulator residues in grapes by ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).Samples were extracted with acetonitrile,and cleaned up on a WAX cartridge.The target analytes were separated on a BEH C18 column with gradient elution using a mobile phase made up of acetonitrile and water.The samples were detected under negative multiple reactions monitoring(MRM)mode through polarity switching between time segments.The result showed that the linearities of gibberellic acid,4-chlorophenoxyaceticacid,forchlorfenuron,and 2,4-dichlorophenoxyacetic were in the concentration range of 1ng/mL~200ng/mL,with the correlation coefficients higher than 0.990.The limits of detection(LOD)and the limits of quantitation(LOQ)of the method were 0.2μg/kg and 0.5μg/kg.The average spiked recovery rates were in the range of 74.8%~101.5%.The result showed that the relative standard deviation(RSD,n=7)was 3.3%~8.6%.The method proved to be simple,sensitive,rapid and suitable for the determination of 4 plant growth regulator residues in grapes.
Key words:Ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS);Plant growth regulator;Grapes
植物生長(zhǎng)調(diào)節(jié)劑(Plant growth regulator,PGRs)是一種能提高農(nóng)產(chǎn)品產(chǎn)量和品質(zhì)的激素[1],主要用于葡萄、獼猴桃、番茄、棉花等,人體如果攝入大量的植物生長(zhǎng)調(diào)節(jié)劑,會(huì)引成腹瀉、免疫力下降等危害,甚至致畸、致癌、致突變等嚴(yán)重后果[2]。近年來,隨著植物生長(zhǎng)調(diào)節(jié)劑在水果、蔬菜等農(nóng)產(chǎn)品中的廣泛和大量使用,其危害性已經(jīng)引起了全社會(huì)民眾的關(guān)注。
目前檢測(cè)植物生長(zhǎng)調(diào)節(jié)劑殘留的常用方法有高效液相色譜法[3]、氣質(zhì)聯(lián)用法[4]和液質(zhì)聯(lián)用法[5-6]。液相色譜法由于抗干擾能力差,存在一定的假陽性;氣質(zhì)聯(lián)用前處理較為復(fù)雜,檢測(cè)時(shí)間較長(zhǎng);液質(zhì)聯(lián)用法對(duì)于物質(zhì)的分析從結(jié)構(gòu)上進(jìn)行確認(rèn),大大降低了假陽性,而且前處理方法簡(jiǎn)單、時(shí)間短,適用于多組分快速檢測(cè)。為此,本研究采用超高效液相色譜-串聯(lián)質(zhì)譜技術(shù)同時(shí)測(cè)定了葡萄中4種植物生長(zhǎng)調(diào)節(jié)劑的殘留量。
1 材料與方法
1.1 材料與試劑 乙腈(HPLC級(jí),德國(guó)MERCK公司);甲醇(HPLC級(jí),德國(guó)CNW公司);WAX小柱(60mg/3mL 美國(guó)Waters公司);氯化鈉、乙酸乙酯為分析純;超純水;4種植物生長(zhǎng)調(diào)節(jié)劑標(biāo)準(zhǔn)品:赤霉素(gibberellic acid,GA3)、對(duì)氯苯氧乙酸(4-chlorophenoxyaceticacid 4-CPA)、氯吡脲(forchlorfenuron)、2,4-二氯苯氧乙酸(2,4-dichlorophenoxyacetic),純度均大于96%(德國(guó)Dr.Ehrenstorfer)。
1.2 儀器與設(shè)備 Waters Xevo TQ-MS 液質(zhì)聯(lián)用儀(美國(guó)Waters公司);高速冷凍離心機(jī)(德國(guó)Sigma公司);氮吹儀(美國(guó)Organomation公司);旋轉(zhuǎn)蒸發(fā)儀(瑞士Buchi公司);勻漿機(jī)(德國(guó)IKA公司);超純水儀(成都超純科技有限公司);超聲儀KQ-600DE(江蘇昆山市超聲儀器公司)。