An electrochemiluminescence aptasensor for amyloid-ll protein with signal enhancement from AuNPs/Fe-MOFs nanocomposite

The aggregation of amyloid-ll protein (All) into amyloid-ll oligomer (AllO) and finally the deposition of amy-loid-ll fiber (AllF) in brain was found strongly related to Alzheimer's disease (AD). In this work, an electro-chemiluminescent (ECL) aptasensor reinforced with a gold nanoparticle - iron metal orgaic framwork nano -composite (AuNPs/Fe-MOFs) was constructed for the detection of All. It has the ability to specifically quantify All, the precursor that had not yet been aggregated into AllO. The employed AuNPs/Fe-MOFs nano-composite in this sensor not only provided the opportunity to anchor the aptamer, but also enhanced the response to pro-mote its sensitivity. The relative inhibition ratio of luminol ECL on this sensor was linearly related to the log-arithm of All concentration in the range from 0.5 to 50 pM, with a LOD at 104 fM. The aptasensor has high specificity to All over its analogs and recoveries in human serum were obtained within 96.0-103.7%. The research prospectively provides a new demonstration for early diagnosis of the disease in clinic.