Highly Sensitive and Specific Amyloid-β Oligomers Detection Using CRISPR-Cas12a Probe System aided by Graphene Oxide for Early Diagnosis of Alzheimer's Diseases

Abstract

Alzheimers disease (AD) is highly age-specific that results in cognitive incapability including dementia. It is proposed that AD is caused by the dysfunctional gene producing excessive amyloid-{beta} protein that eventually results in aggregated form of amyloid-{beta} Oligomers (A{beta}O). We couple the CRISPR-Cas12a system with a specially designed single-stranded DNA (ssDNA) aptamer that specifically forms a hybrid complex with A{beta}O. We exploit the aptamer as the substrate for the crRNA-aptamer duplex due to its high flexibility, sensitivity, and selectivity. We further adopted the graphene oxide (GO) fluorescent system to couple with our CRISPR-Cas12a probe system. Our coupled probe system can effectively detect the presence of A{beta}O by quantitatively returning fluorescent signals with high specificity and accuracy.