在生物技术工艺，如亲和分离和分析领域中，选择具有高选择性和亲和性的配体是非常必要的。用抗体做配体是传统使用的方法，一个强有竞争力的替代方案是使用适配体Aptamer。适配体Aptamer因为其和目标分子的结合特异性和亲和性可被用于各种靶目标的检测和纯化。最新研究阐明了吡咯里西啶生物碱（PAs）肝中毒机制，当PAs作用于肝脏上时可引起肝细胞出血性坏死，肝巨红细胞症，静脉闭塞症及肝窦阻塞综合症等毒性症状。因此如能定性，定量检测天然产物中的PAs将为人类健康的防御做出重大的贡献。目前用于分析PAs的比较先进的方法是运用液相层析串联质谱仪（LC-MSn）。考虑到较为昂贵的设备制备费用，比较难以在各个需要检测PAs的检测点普及，因此需要寻求一种简易廉价的检测方法。适配体Aptamer的技术在此展现了它的适用性和独特性。

High selective and affine ligands are required in biotechnological techniques, including affinity separation and analysis. The conventional methods for affinity-based purification of targets use primarily antibodies. A strongly competitive alternative is the application of aptamers. Because of their binding properties, aptamers can be used to purify and detect different kinds of targets. The previous research illustrates the hepatotoxic mechanism of alkaloids (PAs), although pyrrolizidine alkaloids (PAs) are widespread substances in plant kingdom, they have been found to exhibit hepatotoxicity and genotoxicity. PAs cause liver damage, veno-occlusive disease, especially hepatic sinusoidal obstruction syndrome and other toxic symptoms. Therefore, if PAs can be qualitative and quantitative detected, it could provide a significant contribution for people's health. Currently more advanced method for the analysis of PAs is to use LC-MSn technology. Considering the cost of expensive equipment, this method for detecting PAs is difficult to be disseminated. Therefore to find a simple and inexpensive detection method is very important. In this case, Aptamer technology shows its strong adaptability and uniqueness.