Multifunctional Nitrogen-Doped Carbon Dots to Inhibit\nthe Aggregation of Aβ Peptide and Depolymerize the Aβ\nFibrils by Modulating Reactive Oxygen Species

Multifunctional\nnitrogen-doped carbon dots (N-CDs) were synthesized,\nand the morphology, composition, and spectral properties of N-CDs\nwere characterized by multiple characterization techniques. The inhibition\nof β-amyloid (Aβ) peptide aggregation and the destruction\nof the Aβ fibril structure by N-CDs were also studied. The conformational\ntransition and morphology of Aβ<sub>42</sub> in the presence\nof N-CDs were monitored by far-UV circular dichroism (CD) spectroscopy\nand transmission electron microscopy (TEM). The results demonstrated\nthat the prepared N-CDs could effectively inhibit Aβ<sub>42</sub> peptide aggregation and depolymerize Aβ fibrils. Furthermore,\nthe inhibition and disaggregation mechanism of existing Aβ<sub>42</sub> fibrils by N-CDs was studied by electron paramagnetic resonance\nspectroscopy (EPR). The results showed that the modulation of reactive\noxygen species (ROS) by N-CDs and multiple interactions between N-CDs\nand Aβ<sub>42</sub> fibrils played a crucial part in restraining\nand reducing the aggregation of Aβ<sub>42</sub>. Our work demonstrates\nthe therapeutic potential of N-CDs in suppressing Aβ<sub>42</sub> peptide aggregation and destroying existing Aβ<sub>42</sub> fibrils, which provides a new perspective strategy in the treatment\nof Alzheimer’s disease (AD).