分析化学2026，Vol.54Issue(4)：687-696,10.DOI:10.19756/j.issn.0253-3820.261036
基于靶标响应DNA水凝胶的双霉菌毒素可视化检测
Dual-Mycotoxin Visual Detection Based on Target-Responsive DNA Hydrogel
摘要
Abstract
A visual sensing platform based on competitive binding mechanism between target molecules and single-stranded DNA toward aptamers,using a target-responsive DNA hydrogel as the core molecular recognition element,was developed in this study for respective detection of two mycotoxins,ochratoxin A(OTA)and aflatoxin M1(AFM1).The DNA hydrogel was constructed from linear polyacrylamide-grafted single-stranded DNA backbones(P-S1 and P-S2),which were crosslinked through hybridization with a multifunctional linker strand(Linker 1,L1)containing dual aptamer sequences specific to OTA and AFM1,forming a stable three-dimensional hydrogel network.In the presence of OTA or AFM1,specific binding between target molecules and aptamer domains in L1 reduced the crosslinking density of the DNA hydrogel,leading to hydrogel dissociation and release of pre-encapsulated gold nanoparticles(AuNPs).As a result,the supernatant underwent a visible color change from colorless to the characteristic wine-red color of AuNPs,enabling naked-eye discrimination of target presence.With increasing target concentration,enhanced hydrogel dissociation led to a higher release of AuNPs,allowing rapid quantitative detection of OTA and AFM1 based on the linear relationship between absorbance at 520 nm and target concentration.The proposed sensing platform exhibited a linear detection range of 2-20 μmol/L for OTA with a limit of detection(LOD)of 1.06 μmol/L,and 1-10 μmol/L for AFM1 with a LOD of 0.11 μmol/L.This method required neither sophisticated instrumentation nor expensive reagents,and had advantages including simple preparation,good specificity,and visual readout.Moreover,spike-and-recovery experiments in real samples demonstrated recoveries above 90%,indicating its promising potential for rapid screening of mycotoxin contamination in practical samples.关键词
DNA水凝胶/核酸适配体/赭曲霉毒素A/黄曲霉毒素M1/可视化检测Key words
DNA hydrogel/Aptamer/Ochratoxin A/Aflatoxin M1/Visual detection引用本文复制引用
吴榕,齐丽娟,杜衍..基于靶标响应DNA水凝胶的双霉菌毒素可视化检测[J].分析化学,2026,54(4):687-696,10.基金项目
国家自然科学基金项目(Nos.22322410,22404156,22574151)、吉林省自然科学基金-国家重点实验室(学科类)重大专项(Nos.SKL202302030,SKL202402017)和吉林省与中国科学院科技合作高技术产业化项目(No.2024SYHZ0016)资助. Supported by the National Natural Science Foundation of China(Nos.22322410,22404156,22574151),the Major Project of Jilin Province State Key Laboratory(Nos.SKL202302030,SKL202402017)and the Jilin Province and Chinese Academy of Sciences Science and Technology Cooperation High Tech Special Fund project(No.2024SYHZ0016). （Nos.22322410,22404156,22574151）
