Double Magnetic Separation-assisted Fluorescence Method for Sensitive Detection of Ochratoxin A

• 来源期刊: 高等学校化学研究（英文版）
• 年，卷（期）: 2019,（3）
• 页码范围: 382-389
• 页数: 8页
• 语种: 英文
• DOI: 10.1007/s40242-019-8322-3

摘要

A double magnetic separation-assisted fluorescence method was developed to rapidly detect ochratoxin A(OTA).The OTA aptamer functionalized magnetic nanomaterial(Fe3O4-Aptamer) and complementary DNA conjugated nitrogen-doped graphene quantum dots(NGQDs-cDNA) were used in this assay.Aptamer could hybridize with cDNA,which induced the NGQDs-cDNA to bind onto Fe3O4-Aptamer,and resulted in the fluorescence quenching of NGQDs.After the addition of OTA,the NGQDs-cDNA could release into the solution,and resulted in the recovery of fluorescence signal of NGQDs consequently.By utilizing the magnetic separation,the unbonded NGQDs-cDNA and residual Fe3O4-Aptamer were removed,which significantly increased the fluorescence signal intensity.OTA could be detected in the linear range of 10 nmol/L to 2000 nmol/L,with a linit of detection as 0.66 nmol/L.The advantages of this method include simple operation,good selectivity and high sensitivity,and this method can be used for the rapid detection of ochratoxin A in wheat and corn.