Nanoparticles Self-Assembly Driven by High Affinity Repeat Protein Pairing

Kargal L. Gurunatha (1) , Agathe C. Fournier (1) , Agathe Urvoas (2) , Marie Valerio-Lepiniec (2) , Valérie Marchi (3) , Philippe Minard (2) , Erik Dujardin (1)

1 CEMES - Centre d'élaboration de matériaux et d'études structurales
2 I2BC - Institut de Biologie Intégrative de la Cellule
3 ISCR - Institut des Sciences Chimiques de Rennes

Proteins are the most specific yet versatile biological self-assembling agents with a rich chemistry. Nevertheless, the design of new proteins with recognition capacities is still in its infancy and has seldom been exploited for the self-assembly of functional inorganic nanoparticles. Here, we report on the protein-directed assembly of gold nanoparticles using purpose-designed artificial repeat proteins having a rigid but modular 3D architecture. αRep protein pairs are selected for their high mutual affinity from a library of 10(9) variants. Their conjugation onto gold nanoparticles drives the massive colloidal assembly of free-standing, one-particle thick films. When the average number of proteins per nanoparticle is lowered, the extent of self-assembly is limited to oligomeric particle clusters. Finally, we demonstrate that the aggregates are reversibly disassembled by an excess of one free protein. Our approach could be optimized for applications in biosensing, cell targeting, or functional nanomaterials engineering

Keywords: dissociation constant; gold nanoparticles; protein pair; reversible self-assembly; α-repeat proteins

Domains: Chemical Sciences; Material chemistry

Kargal L. Gurunatha, Agathe C. Fournier, Agathe Urvoas, Marie Valerio-Lepiniec, Valérie Marchi, et al.. Nanoparticles Self-Assembly Driven by High Affinity Repeat Protein Pairing. ACS Nano, 2016, 10 (3), pp.3176-3185. ⟨10.1021/acsnano.5b04531⟩. ⟨hal-01274834⟩