- Journal
- ANALYTICAL CHEMISTRY
- Année
- 2023
- Mois
- 2023 AUG 16
- DOI
- 10.1021/acs.analchem.3c00017
Abstract
Inthis work, early-stage A & beta;42 aggregates weredetected usinga real-time fast amyloid seeding and translocation (RT-FAST) assay.Specifically, A & beta;42 monomers were incubated in buffer solutionwith and without preformed A & beta;42 seeds in a quartz nanopipettecoated with L-DOPA. Then, formed A & beta;42 aggregates were analyzedon flyby resistive pulse sensing at various incubation time points.A & beta;42 aggregates were detected only in the sample with A & beta;42seeds after 180 min of incubation, giving an on/off readout of thepresence of preformed seeds. Moreover, this RT-FAST assay could detectpreformed seeds spiked in 4% cerebrospinal fluid/buffer solution.However, in this condition, the time to detect the first aggregateswas increased. Analysis of Cy3-labeled A & beta;42 monomer adsorptionon a quartz substrate after L-DOPA coating by confocal fluorescencespectroscopy and molecular dynamics simulation showed the huge influenceof A & beta;42 adsorption on the aggregation process.