MULTIPLE RAMAN DETECTION METHOD BASED ON SILVER NANOPARTICLE TETRAHEDRON

摘要

A multiple Raman detection method based on silver nanoparticle tetrahedron. The silver nanoparticle tetrahedron is prepared in the method by nanoparticles self-assembly mediated through DNA. By the use of spatial configuration of the tetrahedron, three DNA fragments containing nucleic aptamers for respectively sulphadimethoxine (SDM), aflatoxin M1 (AFM1) and ochratoxin (OTA) to be tested and three molecular beacons are used in the silver nanoparticle tetrahedron so as to construct the multiple Raman detection system based on silver nanoparticle tetrahedron. When there is substance to be tested, the change of Raman signal is detected, and the change responds to the tetrahedral spatial configuration alteration. The Raman signal alterations of three molecular beacons correspond to the concentrations of three target substrates so as to achieve the simultaneous detection of three target substrates SDM, AFM1 and OTA. With the method, high sensitivity and good specificity are achieved to facilitate application of the Raman sensing technique in practice, without disorderly aggregation of nanoparticles.