We have developed an aptamer affinity column (AAC) for the purification and enrichment of trace aflatoxin B1 (AFB1) and aflatoxin B2 (AFB2) in genuine agro-products through the covalent conjugation of amino modified aptamer and NHS-activated Sepharose. The coupling and working conditions found to be suitable for this AFB-AAC were examined in regard to coupling time (2 min), loading volume (30 mL), and the methanol concentration (< 10%) used in the loading step. The performance of AFB-AAC was then further evaluated in terms of capacity (329.1 ± 13.7 ng for AFB1 and 162.5 ± 8.9 ng for AFB2), selectivity (excellent), reusability (twenty-three times for AFB1 and twelve times for AFB2), and repeatability (92.7% ± 2.9% for AFB1 and 71.5% ± 3.4% for AFB2). Furthermore, the AAC clean-up combined with HPLC-FLD demonstrated excellent linearity over a wide range, good sensitivity with an LOD of 50 pg mL-1 for AFB1 and 15 pg mL-1 for AFB2, and acceptable recovery with different spiking levels in different matrices. Finally, the AAC was successfully applied to analyte AFB1 and AFB2 in four types of agro-products as well as a maize flour reference material, and the results were found to be in accordance with those of commercial IACs. This study provides a reference for the analysis of other trace analytes by merely changing the corresponding aptamer and represents a strong contender for immune affinity columns. Graphical abstract An aptamer affinity column for purification and enrichment of aflatoxin B1 and aflatoxin B2 in agro-products with the aid of HPLC-FLD and a post-column photochemical derivatization reactor.

中文翻译：

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适体亲和柱，用于纯化和富集农产品中的黄曲霉毒素B1和黄曲霉毒素B2。

我们开发了一种适体亲和柱（AAC），用于通过氨基修饰的适体和NHS活化的Sepharose的共价缀合纯化和富集真正农产品中的痕量黄曲霉毒素B1（AFB1）和黄曲霉毒素B2（AFB2）。关于偶联时间（2分钟），加样量（30 mL）和加样步骤中使用的甲醇浓度（<10％），检查了适用于该AFB-AAC的偶联和工作条件。然后，根据容量（AFB1为329.1±13.7 ng，AFB2为162.5±8.9 ng），选择性（优异），可重用性（AFB1为23倍，AFB2为12倍）进一步评估了AFB-AAC的性能，和可重复性（AFB1为92.7％±2.9％，AFB2为71.5％±3.4％）。此外，AAC净化与HPLC-FLD结合使用，在宽范围内显示出优异的线性度，对AFB1的LOD为50 pg mL-1，对AFB2的LOD为15 pg mL-1的灵敏度很高，并且在不同基质上具有不同加标水平的回收率均可接受。最后，将AAC成功应用于四种农产品和玉米粉参考物质中的分析物AFB1和AFB2，发现结果与商业IAC一致。该研究仅通过改变相应的适体即可为其他痕量分析物的分析提供参考，并代表了免疫亲和柱的强大竞争者。图形摘要借助HPLC-FLD和柱后光化学衍生化反应器纯化和富集农产品中黄曲霉毒素B1和黄曲霉毒素B2的适体亲和柱。