|
| Electrochemical Genosensing for Duo-Amplification Signal of CaMV 35S Sequence in Genetically Modified Organism |
| |
| View Full Text Download reader |
| DOI： |
| KeyWord:genetically modified organism（GMO） electrochemical genosensor reduced graphene oxide gold nanoparticle（AuNP） thionine hemin label-free |
| Author | Institution |
| ZHENG Hai-song，XIE Jing-qi，SUN Juan-juan，YE Yong-kang，CAO Xiao-dong |
1. Technology Center of Hefei Customs District， Hefei ， China; 2. School of Food and Biological Engineering， Hefei University of Technology， Hefei ， China |
|
| Hits: 1357 |
| Download times: 625 |
| Abstract: |
| A novel electrochemical genosensor was designed and fabricated for the detection of transgenic cauliflower mosaic virus 35S（CaMV 35S） promoter in this paper. Firstly， hemin functionalized reduced graphene oxide（Hemin－rGO） was prepared and modified onto the surface of a glassy carbon electrode（GCE）. And then， gold nanoparticles（AuNP） were electro-deposited on the surface of the Hemin－rGO to immobilize the thiolated capture DNA. By designing a sandwich-type sensing strategy， when the target sequence was present， the auxiliary DNA hybridized with the target and capture probe to form a double-strand and used its thiolated 5'-end to covalently bind to AuNP. Meanwhile， the amplified current response for the sensitive detection target CaMV 35S promoter sequence was obtained when the former was loaded with thionine（Thi）. Effects of buffer pH value， Thi concentration， soaking time of AuNP， and incubation time of DNA sequences were investigated. The optimal conditions were as follows： pH 7.4， Thi concentration ：0.5 mmol/L， soaking time of AuNP：40 min， incubation time of DNA sequences：60 min. Under the optimal conditions， there was a good linear relationship between DPV peak current and logarithms of the target concentration in the range of 1 × 10－16－1 × 10－10 mol/L， with a detection limit of 9.46 × 10－17 mol/L. The genosensor was applied to the detection of CaMV 35S promoter sequence in transgenic Arabidopsis samples with high selectivity， good stability and repeatability. The results obtained were consistent with those of the gel electrophoresis. This method has a good application prospect in the rapid detection and screening of genetically modified organism（GMO） ingredients in food， feed and other industrial products. |
| Close |