论文部分内容阅读
A label free and tetrahedron DNA nanostructure(3 D-DNA) coupling with hybridization chain reaction(HCR) amplification strategy was developed for carinoembryonic antigen(CEA) detection. The magnetic beads(MB) probe, which was attached the aptamer of CEA and m DNA, was firstly fabricated. 3 D–DNA, as a base of the capture probe was modified on the electrode surface through Au-S bond. Here, it provided steady support and optimized surface density for the very "large" complex of HCR system. In the presence of CEA, m DNA was released from MB upon recognition of the aptamer to target CEA. The released mDNA hybridizes with the vertical domain of 3 D-DNA and its trigger action to HCR, leading to formation numerous G-quadruplex DNA mimic enzyme with the presence of hemin. Therefore, an electrochemical signal through the developed strategy would be achieved. While without CEA, m DNA would remind. There would have no electrochemical signal, due to HCR did not occur. The proposed platform was simple and convenient, which was hopeful to apply in biotechnology and clinical diagnosis.