基于核酸适配体修饰复合纳米纤维的分散固相萃取技术在赭曲霉毒素A检测中的应用  

Dispersive Solid-Phase Extraction Technology Based on Aptamer Modified Composite Nanofibers and Its Application in Detection of Ochratoxin A

作　　者：刘炉英 刘锦辉 胡小刚[2] LIU Lu-Ying;LIU Jin-Hui;HU Xiao-Gang(Department of Chemistry,Guangdong University of Education,Guangzhou 510303,China;School of Chemistry,South China Normal University,Guangzhou 510631,China;Analysis&Testing Center,South China Normal University,Guangzhou 510631,China)

机构地区：[1]广东第二师范学院化学系,广州510303 [2]华南师范大学化学学院,广州510631 [3]华南师范大学分析测试中心,广州510631

出　　处：《分析化学》2021年第12期2096-2105,共10页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(Nos.21775048,21275058);广东省自然科学基金项目(No.2017A030313060);广东省科技计划项目(No.2013B091500093);广州市科技计划项目(No.201904010166);广东省普通高校青年创新人才项目(No.2018KQNCX178)资助。

摘　　要：采用冷冻干燥法制备壳聚糖-海藻酸钠复合纳米纤维,此纤维呈均匀丝状结构,宽度约0.4μm。通过化学键合方式将赭曲霉毒素A(Ochratoxin A,OTA)核酸适配体固载于纳米纤维表面,制备得到核酸适配体修饰的壳聚糖-海藻酸钠复合纳米纤维材料,适配体键合量达到2.3μg/mg,可作为分散固相萃取吸附剂。此吸附剂对OTA表现出良好的萃取能力及高选择性,萃取容量约为3.1 ng/mg,萃取量为结构类似物赭曲霉毒素B及5种参照物分子的2.44~12.8倍,相比随机序列修饰的复合纳米纤维以及复合纳米纤维,OTA的萃取量分别提高了4.88和13.0倍。在最佳萃取实验条件下,建立了基于核酸适配体修饰复合纳米纤维分散固相萃取-高效液相色谱测定OTA的分析方法,线性范围为0.05~3.0μg/L,检出限(LOD,S/N=3)为13 ng/L,加标回收率为86.7%~101.0%。本方法选择性好、灵敏度高,可用于花生、玉米和小麦等样品中痕量OTA的检测。The chitosan-sodium alginate composite nanofibers were prepared by freeze-drying.The nanofibers had a uniform filamentous structure with a width of about 0.4μm.The aptamer of ochratoxin A was immobilized on the surface of the fiber by chemical bonding to obtain the aptamer-modified chitosan-sodium alginate composite nanofiber,and the bonding amount of the aptamer could reacH_(2).3μg/mg.It could be used as an adsorbent for dispersive solid phase extraction technology.The adsorbent showed good extraction ability and high selectivity for ochratoxin A,the extraction capacity was about 3.1 ng/mg,and the extraction amount was 2.44-12.8 times of the structural analogue ochratoxin B and the five reference molecules.Compared with the composite nanofiber modified by the scrambled oligonucleotide and composite nanofiber,the extraction amount of ochratoxin A was increased by 4.88 and 13.0 times,respectively.Under the optimal extraction conditions,an analytical method based on aptamer modified composite nanofiber dispersion solid phase extraction-high performance liquid chromatography for determination of ochratoxin A was established.The linear range was 0.05-3.0μg/L,the detection limit was 13 ng/L(S/N=3),and the recoveries of standard addition were 86.7%-101.0%.This method had good selectivity and high sensitivity,and could be applied to the detection of trace ochratoxin A in peanut,corn and wheat samples.

关 键 词：复合纳米纤维 核酸适配体 分散固相萃取 赭曲霉毒素A 

分 类 号：O658.2[理学—分析化学] O657.72[理学—化学] TS210.7[轻工技术与工程—粮食、油脂及植物蛋白工程]