Zhang Wenpeng, Li Yilin, Chen Zilin
Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan, China.
State Key Laboratory of Transducer Technology, Chinese Academy of Sciences, Beijing, China.
J Sep Sci. 2015 Nov;38(22):3969-3975. doi: 10.1002/jssc.201500864. Epub 2015 Oct 19.
In this work, we developed a novel molecularly imprinted solid-phase microextraction with capillary electrophoresis method for the selective extraction and determination of protoberberines in complicated samples. The imprinted monolith was prepared in a micropipette tip-based device by using acrylamide as the functional monomer, ethyleneglyoldimethacrylate as the cross-linker and dimethylsulfoxide as the porogen, and exhibited an imprinting factor of 2.41 to berberine, 2.36 to palmatine and 2.38 to jatrorrhizine. Good capillary electrophoresis separation was achieved by using 20 mM phosphate buffer at pH 7 as running buffer with the addition of organic modifier of 10% methanol. Parameters such as sample pH value, sample flow rate and sample volume were investigated for imprinted monolith-based solid-phase microextraction. An imprinted solid-phase microextraction with capillary electrophoresis method was developed, the method showed a wide linear range (0.3-50 μg/mL), good linearity (R ≥ 0.9947) and good reproducibility (relative standard deviations ≤ 0.73%), the limit of detection was as low as 0.1 μg/mL, which was lower than some reported methods based on capillary electrophoresis for protoberberines. The method has been applied for determination of three common protoberberines in Cortex Phellodendri Chinensis, by using a molecularly imprinted monolith as the selective sorbent, most of the matrices in the Cortex Phellodendri Chinensis sample were removed and three protoberberines were selectively enriched and well determined.
在本研究中，我们开发了一种新型的分子印迹固相微萃取-毛细管电泳方法，用于复杂样品中原小檗碱类生物碱的选择性萃取和测定。以丙烯酰胺为功能单体、乙二醇二甲基丙烯酸酯为交联剂、二甲基亚砜为致孔剂，在基于微量移液器吸头的装置中制备了印迹整体柱，该整体柱对小檗碱的印迹因子为2.41，对巴马汀的印迹因子为2.36，对药根碱的印迹因子为2.38。采用pH 7的20 mM磷酸盐缓冲液作为运行缓冲液，并添加10%甲醇作为有机改性剂，实现了良好的毛细管电泳分离。考察了样品pH值、样品流速和样品体积等参数对基于印迹整体柱的固相微萃取的影响。建立了一种分子印迹固相微萃取-毛细管电泳方法，该方法线性范围宽（0.3 - 50 μg/mL），线性良好（R≥0.9947），重现性好（相对标准偏差≤0.73%），检测限低至0.1 μg/mL，低于一些已报道的基于毛细管电泳的原小檗碱类生物碱测定方法。该方法已用于黄柏中三种常见原小檗碱类生物碱的测定，以分子印迹整体柱作为选择性吸附剂，去除了黄柏样品中的大部分基质，选择性富集并良好测定了三种原小檗碱类生物碱。
