A hydrogel biosensor for high selective and sensitive detection of amyloid-beta oligomers.

ABSTRACT: Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive cognitive and memory impairment. It is the most common neurological disease that causes dementia. Soluble amyloid-beta oligomers (A?O) in blood or cerebrospinal fluid (CSF) are the pathogenic biomarker correlated with AD.A simple electrochemical biosensor using graphene oxide/gold nanoparticles (GNPs) hydrogel electrode was developed in this study. Thiolated cellular prion protein (PrPC) peptide probe was immobilized on GNPs of the hydrogel electrode to construct an A?O biosensor. Electrochemical impedance spectroscopy was utilized for A?O analysis.The specific binding between A?O and PrPC probes on the hydrogel electrode resulted in an increase in the electron-transfer resistance. The biosensor showed high specificity and sensitivity for A?O detection. It could selectively differentiate A?O from amyloid-beta (A?) monomers or fibrils. Meanwhile, it was highly sensitive to detect as low as 0.1 pM A?O in artificial CSF or blood plasma. The linear range for A?O detection is from 0.1 pM to 10 nM.This biosensor could be used as a cost-effective tool for early diagnosis of AD due to its high electrochemical performance and bionic structure.

SUBMITTER: Sun L 

PROVIDER: S-EPMC5811178 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature