Institute of analytical technology and smart instruments, Xiamen Huaxia University, Xiamen, 361024, China.
Institute of Food Safety and Environment Monitoring, Fuzhou University, Fuzhou, 350108, China.
J Chromatogr A. 2021 Feb 22;1639:461930. doi: 10.1016/j.chroma.2021.461930. Epub 2021 Jan 22.
Herein, a facile and practical aptamer-grafted ionic affinity monolith with mixed-mode mechanism was explored as a versatile platform for online specific recognition of polar and non-polar mycotoxins. The mixed-mode mechanism including molecular affinity adsorption (between aptamers and targets), hydrophilic interaction and ionic interaction (between stationary phase and targets) were adopted and provided a better flexibility in adjusting separation selectivity to reduce nonspecific adsorption with respect to the single mode. Preparation and characterization of aptamer-based affinity monoliths were investigated, The characterization of pore size distribution, Brunauer-Emmett-Teller (BET) surface area and the specificity and cross-reaction were also evaluated. As a result, the hydrophilic nature and negative charge on affinity monolith were obtained. Multiple interactions including aptamer affinity binding, hydrophilic interaction (HI) and ion exchange (IE) could be adopted for online selective extraction. Specific recognitions of polar ochratoxin A (OTA), non-polar zearalenone (ZEN) and aflatoxin B1 (AFB1) was fulfilled with LODs as 0.03, 0.05 and 0.05 μg/L, respectively. Applied to real cereals, good recoveries of the fortified OTA, AFB1 and ZEN were achieved as 92.6 ± 1.3% ~ 95.6 ± 1.3% (n=3), 93.9 ± 2.3% ~ 98.2 ± 3.4% (n=3) and 92.7 ± 2.0% ~ 96.9 ± 3.5% (n=3) in corn, wheat and rice, respectively. The results displayed that Apt-MCs with hydrophilic and ionic interaction mixed-mode mechanism were efficient enough and competent for the online recognition of mycotoxins in cereals.
本文探索了一种简便实用的适体接枝离子亲和整体柱，具有混合模式机制，可作为在线特异性识别极性和非极性真菌毒素的通用平台。混合模式机制包括分子亲和吸附（适体与靶标之间）、亲水相互作用和离子相互作用（固定相与靶标之间），为调整分离选择性以减少非特异性吸附提供了更大的灵活性。本文研究了基于适体的亲和整体柱的制备和表征，还评价了孔径分布、BET 表面积以及特异性和交叉反应的特性。结果表明，亲和整体柱具有亲水性和负电荷。多种相互作用，包括适体亲和结合、亲水相互作用（HI）和离子交换（IE），可用于在线选择性提取。实现了对极性的赭曲霉毒素 A（OTA）、非极性的玉米赤霉烯酮（ZEN）和黄曲霉毒素 B1（AFB1）的特异性识别，LOD 分别为 0.03、0.05 和 0.05 μg/L。应用于实际谷物，OTA、AFB1 和 ZEN 的加标回收率分别为 92.6±1.3%95.6±1.3%（n=3）、93.9±2.3%98.2±3.4%（n=3）和 92.7±2.0%~96.9±3.5%（n=3），在玉米、小麦和大米中均较高。结果表明，具有亲水和离子相互作用混合模式机制的 Apt-MCs 足以实现谷物中真菌毒素的在线识别。
