纳米金标记DNA的生物传感器

BIOSENSOR USING GOLD NANOPARTICLE-OLIGONUCLEOTIDE DNA

目的利用纳米金标记DNA以提高传感器的检测灵敏度,为建立方便、快速、准确地检测食品中李斯特菌的方法提供依据。方法利用自组装法,将5′端巯基修饰的单链DNA固定在金电极上,然后与纳米金标记的探针进行杂交。结果传感器与标记有胶体金的探针杂交频率减少了207 Hz,与未标记有胶体金探针杂交频率(减少了52 Hz)相比提高了3倍。结论采用纳米金标记的探针可提高传感器的检测灵敏度,在食品安全检测中具有重要意义。

Objective To improve the sensitivity of biosensor by using gold nanoparticle - olgonucleotide DNA, so as to provide the basis for establishing a convenient, rapid and accurate method for detecting Listeria monocytogenes in food. Methods DNA single strand marked with thiol group at the 5＇ end was immobilized on the surface of gold electrode. The electrode were hybridized with gold nanoparticle-oligonucleotide DNA probes in this DNA biosensor. Results The frequency of DNA biosensor with labeled gold nanoparticle - oligonucleotide DNA probe decreased by 207 Hz, which was 3 times as high as unlabeled probe（52 Hz）. Conclusion The sensitivity of DNA biosensor with gold nanoparticle - oligonucleotide DNA probe is obviously improved. It is of importance in detection of food safety.