Highly sensitive detection of ochratoxin A based on bio-barcode immunoassay and catalytic hairpin assembly signal amplification
Talanta(2020)
摘要
Herein, a highly sensitive ochratoxin A (OTA) detection strategy was developed based on a bio-barcode immunoassay with catalytic hairpin assembly (CHA). Two nanoprobes were designed for the assay: one was a gold nanoparticle (AuNP) harbouring numerous bio-barcode DNA and antibodies, and the other was an antigen-functionalized magnetic nanoparticle (MNP). In the presence of target OTA, the antigens of the MNPs competed with OTA for binding to the antibodies on the AuNPs. After magnetic separation, the unbound AuNPs and target OTA were washed away. Dithiothreitol (DTT) was then added to the MNP-bound AuNPs to elute the bio-barcode DNAs of AuNPs, which triggered the CHA reaction. Under optimal conditions, the proposed method could sensitively detect target OTA ranging from 0.001 to 10000 ng/mL. The limit of detection (LOD, 3 N/S) and limit of quantification (LOQ, 10 N/S) for OTA were 0.54 pg/mL and 1.80 pg/mL, respectively. The bio-barcode immunoassay was used to analyse food samples (corn, wheat, and peanut), and the recovery and relative standard deviations (RSD) ranged from 93.30% to 108.80% and from 3.2% to 6.9%, respectively. The total assay time was 6 h. Therefore, the proposed strategy will provide a new approach for the detection of mycotoxins and other small molecule analytes and can be applied for quality control to ensure food safety.
更多查看译文
关键词
Bio-barcode immunoassay,Catalytic hairpin assembly,Nanoparticles,Ochratoxin A (OTA)
AI 理解论文
溯源树
样例
![](https://originalfileserver.aminer.cn/sys/aminer/pubs/mrt_preview.jpeg)
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要