| 초록 |
Alzheimer’s disease (AD) is the most common form of dementia and currently affects about 500,000 Korean over 65 age. So, the highly-sensitive biosensors deserved to be developed because the early diagnosis of AD is becoming very important. Amyloid beta (Aβ) peptide which is directly related to AD is considered as an emerging AD marker, but it is delicate to detect it without secondary labels like fluorophores. Here, we prepared peroxidase-mimetic gold nanoparticle-decorated peptide self-assembly nanostructure (PEPAu/Sat) based fluorescence turn-on sensor for the label-free detection of Aβ(1-42) as AD marker. The detection mechanism largely composed of oxidation of Aβ(1-42) by Fe(III) or Cu(II), which produce hydrogen peroxide from dissolved oxygen in situ, and sequential oxidation of Amplex Red (AR) by the gold nanoparticles coupled on PEPAu/Sat to emit fluorescence around 585 nm. To apply this novel mechanism to Aβ(1-42) biosensor, anti-Aβ(1-42) antibody was immobilized on PEPAu/Sat and Aβ(1-42) was captured by them. We hope this novel biosensor platform can expand their applications to other disease markers including cancers. |
