液相色谱-串联质谱法测定花粉中的链霉素和双氢链霉素

Determination of streptomycin and dihydrostreptomycin in pollens byhighperformance liquid chromatographytandem mass spectrometry

建立了花粉中链霉素（ streptomycin，STR）与双氢链霉素（ dihydrostreptomycin，DHS）的高效液相色谱-串联质谱（HPLC-MS / MS）检测方法。样品经提取液提取、三氯甲烷沉淀蛋白后，用 C18固相萃取柱进行富集净化，采用 HPLC-MS / MS 对目标物进行定性确证和定量分析。在 Protemix WCX-NP5色谱柱（100 ×2.1 mm，5μm）上以5％（v / v）甲酸、20 mmol / L 醋酸铵和甲醇为流动相进行梯度洗脱分离；质谱采集模式为电喷雾正离子监测模式。链霉素和双氢链霉素的检出限（以信噪比（ S / N）＝3计）均为5μg / kg，定量限（以 S / N ＝10计）均为10μg / kg；在10~200μg / L 的质量浓度范围内呈现良好的线性关系，相关系数（ r）大于0.99。本底空白的松花粉、玉米花粉、茶花粉、葵花粉、油菜花粉、杂花粉等6种基质中10、20、50μg / kg 添加水平下的加标回收率范围为76.8％~100.3％，精密度范围为3.70％~12.6％。该方法无需使用对 LC-MS 联用仪容易造成污染的七氟正丁酸，且方法准确可靠，适用于大部分花粉基质的测定。

A method was established for the determination of streptomycin（STR）and dihydro-streptomycin（DHS）in pollens based on high performance liquid chromatography-tandem mass spectrometry（HPLC-MS / MS）. The sample was extracted and cleaned-up by a C18 solid phase extraction cartridge. The separation was carried out on a Protemix WCX-NP5 column（100 mm ×2. 1 mm,5 μm）with a gradient elution using 5% （ v / v）formic acid,20 mmol / L ammonium acetate and methanol as mobile phases. The analysis of streptomycin and dihydrostreptomycin was performed under electrospray positive ionization mode. The limits of detection（LOD,S / N= 3）and limits of quantification（ LOQ,S / N = 10）for the both were 5 μg / kg and 10 μg / kg, respectively. Good linearities（r ﹥0. 99）were achieved for the target compounds over the range of 10-200 μg / L. The recoveries at three spiked levels（10,20,50 μg / kg）in the blank matri-ces,such as pollen pini,corn pollen,camellia pollen,sunflower pollen,rape pollen and bee pollen,were from 76. 8% to 100. 3% with the relative standard deviations varied from 3. 70% to 12. 6% . The method is accurate,practical,and can be applied to most of the contaminated＆amp;nbsp;matrices. With this method,heptafluorobutyric acid is not required as mobile phase which is harmful to MS spectrometer.