Posted by Recognition and capture of amyloid beta is a challenging task for the early diagnosis of neurodegenerative disorders, such as Alzheimer’s disease. Here we report a novel KLVFF-modified nanomagnet based on magnetic nanoparticles (MNP) covered with a non-ionic amphiphilic beta-cyclodextrin (SC16OH) and decorated with KLVFF oligopeptide for the self-recognition of the homologous aminoacids sequence of amyloid beta to collect amyloid beta (1–42) peptide from aqueous samples. MNP@SC16OH and MNP@SC16OH/Ada-Pep nanoassemblies were fully characterized by complementary techniques both as solid powders and in aqueous dispersions. Single domain MNP@SC16OH/Ada-Pep nanomagnets of 20–40 nm were observed by TEM analysis. DLS and zeta-potential measurements revealed that MNP@SC16OH nanoassemblies owned in aqueous dispersion a hydrodynamic radius of about 150 nm, which was unaffected by Ada-Pep decoration, while the negative zeta-potential of MNP@SC16OH (-40 mV) became less negative (- 30 mV) in MNP@SC16OH/Ada-Pep, confirming the exposition of positively charged KLVFF on nanomagnets surface. The ability of MNP@SC16OH/Ada-Pep to recruit amyloid beta (1–42) in aqueous solution was evaluated by MALDI-TOF and compared with the ineffectiveness of undecorated MNP@SC16OH and VFLKF scrambled peptide-decorated nanoassemblies (MNP@SC16OH/Ada-scPep), pointing out the selectivity of KLVFF-decorated nanohybrid towards amyloid beta (1–42). Finally, the property of nanomagnets to extract amyloid beta in conditioned medium of cells over-producing amyloid beta peptides was investigated as proof of concept of effectiveness of these nanomaterials as potential diagnostic tools.
Antonino Mazzaglia, Giuseppe Di Natale, Rita Tosto, Angela Scala, Giuseppe Sortino, Anna Piperno, Maria Pia Casaletto, Alberto Riminucci, Maria Laura Giuffrida, Placido G. Mineo, Valentina Villari, Norberto Micali, Giuseppe Pappalardo: Thiolated amphiphilic beta-cyclodextrin-decorated gold colloids: Synthesis, supramolecular nanoassemblies and controlled release of dopamine. Journal of Colloid and Interface Science 613 (2022) 814–826. https://doi.org/10.1016/j.jcis.2022.01.051