Beijing National Laboratory for Molecular Sciences, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, PR China.
Talanta. 2012 Sep 15;99:420-5. doi: 10.1016/j.talanta.2012.05.073. Epub 2012 Jun 7.
In this work, a new labeling reagent, 2-bromopyridine-5-boronic acid (BPBA), was introduced to derivatize brassinosteroids (BRs). The BPBA not only provided a very simple and rapid labeling procedure, but also remarkably increased the detection sensitivity of BRs. Based on this new labeling reaction, a rapid and sensitive method for BRs' analysis in Arabidopsis thaliana was established by using the ultra high performance liquid chromatography-electrospray ionization triple quadrupole mass spectrometry (UHPLC-ESI-QqQ-MS). The extraction and purification procedure of the plant sample was also simplified and improved in this work. Good linearities were obtained for three BRs with the determination coefficients (R(2)) about 0.9999. The limits of detection (S/N=3) for three BRs were found to be 2.00-8.00 ng/L while the limits of quantification (S/N=10) were 6.00-23.0 ng/L. The RSD % for all three samples are lower than 8.67% (n=5). The recoveries of three BRs spiked in A. thaliana samples were from 76.9% to 86.1%. Using this method, the endogenous 0.055 ng/g fresh weight (FW) 24-epiBR and 0.070 ng/g (FW) 28-epihomoBR were successfully detected from only 2g A. thaliana plants.
在这项工作中，引入了一种新的标记试剂 2-溴吡啶-5-硼酸（BPBA），用于衍生油菜素内酯（BRs）。BPBA 不仅提供了一种非常简单和快速的标记程序，而且还显著提高了 BRs 的检测灵敏度。基于这种新的标记反应，通过使用超高效液相色谱-电喷雾电离三重四极杆质谱（UHPLC-ESI-QqQ-MS），建立了一种用于拟南芥中 BRs 分析的快速灵敏方法。在这项工作中，还简化和改进了植物样品的提取和纯化程序。三种 BRs 的提取和纯化程序得到了很好的线性关系，决定系数（R(2)）约为 0.9999。三种 BRs 的检测限（S/N=3）分别为 2.00-8.00ng/L，定量限（S/N=10）分别为 6.00-23.0ng/L。所有三种样品的 RSD%均低于 8.67%（n=5）。三种 BRs 加标于拟南芥样品中的回收率在 76.9%至 86.1%之间。使用该方法，仅从 2g 拟南芥植物中成功检测到 0.055ng/g 鲜重（FW）24-epiBR 和 0.070ng/g（FW）28-epihomoBR 的内源性物质。
