The interaction of β2-microglobulin with gold nanoparticles: Impact of coating, charge and size

Cristina Cantarutti, Paolo Bertoncin, Paola Posocco, Yamanappa Hunashal, Sofia Giorgetti, Vittorio Bellotti, Federico Fogolari, Gennaro Esposito

Research output: Contribution to journalArticlepeer-review


Gold nanoparticles (AuNPs) have been proved to be ideal scaffolds to build nanodevices whose performance can be tuned by changing their coating. In particular, the interaction of AuNPs with proteins was revealed to be highly dependent on the physico-chemical properties of the gold cluster protecting monolayer. In this work we studied the behavior of three different alkanethiolate-coated AuNPs (AT-AuNPs) when they are incubated with a model amyloidogenic protein, β2-microglobulin (β2m), whose clinical relevance in dialysis-related amyloidosis (DRA) and structural properties are well known. To the aim we synthesized 6-mercaptohexanoic acid-coated AuNPs (MHA-AuNPs) and (11-mercaptoundecyl)-N,N,N-trimethylammonium bromide-coated AuNPs (MUTAB-AuNPs) of 7.5 nm diameter and 3-mercaptopropionic acid-coated AuNPs (MPA-AuNPs) of 3.6 nm diameter. To study the effects of the incubation with β2m of these NPs that differ in charge and dimension, we employed NMR, UV-vis and fluorescence spectroscopy, along with transmission electron microscopy (TEM). The three tested AuNP systems gave different results. We found that MHA-AuNPs precipitate with the protein into large agglomerates inducing β2m unfolding, MUTAB-AuNP precipitation is triggered by the protein that remains unchanged in solution, at least at the higher considered protein/NP ratio, and MPA-AuNPs interact preferentially with a localized region of the protein that stays essentially stably dissolved. These results stress the complexity of the bio-nano interface and the relevance and viability of the fine control of NP properties to master protein-NP interactions.

Original languageEnglish (US)
Pages (from-to)5964-5974
Number of pages11
JournalJournal of Materials Chemistry B
Issue number37
StatePublished - 2018

ASJC Scopus subject areas

  • General Chemistry
  • Biomedical Engineering
  • General Materials Science


Dive into the research topics of 'The interaction of β2-microglobulin with gold nanoparticles: Impact of coating, charge and size'. Together they form a unique fingerprint.

Cite this