KCS

Recently development on detection and quantitation of mycotoxins which produced by fungus in a variety of commodities has received great attention from reseachers. Here, we report a new approach for the detection of Ochratoxin A (OTA) using surface-enhanced Raman scatteing (SERS) that could exhibit lower detection limits than fluorescence method. This approach is based on conformation change of Raman reporter-tagged Ochratoxin A (OTA)’s aptamer. OTA’s aptamer could be easily adsorbed onto the surface of metal nanoparticles (NPs), and give good SERS signal. Upon the addition of OTA, however, the conformation of OTA’s aptamer is changed from random coil structure to G-quadruplex structure. Thus OTA’s aptamer could not be adsorbed onto the surface of NPs, and SERS signal will be decreased.