Skip to Content
Merck
  • Nucleation of iron oxide nanoparticles mediated by Mms6 protein in situ.

Nucleation of iron oxide nanoparticles mediated by Mms6 protein in situ.

ACS nano (2014-08-28)
Sanjay Kashyap, Taylor J Woehl, Xunpei Liu, Surya K Mallapragada, Tanya Prozorov
ABSTRACT

Biomineralization proteins are widely used as templating agents in biomimetic synthesis of a variety of organic-inorganic nanostructures. However, the role of the protein in controlling the nucleation and growth of biomimetic particles is not well understood, because the mechanism of the bioinspired reaction is often deduced from ex situ analysis of the resultant nanoscale mineral phase. Here we report the direct visualization of biomimetic iron oxide nanoparticle nucleation mediated by an acidic bacterial recombinant protein, Mms6, during an in situ reaction induced by the controlled addition of sodium hydroxide to solution-phase Mms6 protein micelles incubated with ferric chloride. Using in situ liquid cell scanning transmission electron microscopy we observe the liquid iron prenucleation phase and nascent amorphous nanoparticles forming preferentially on the surface of protein micelles. Our results provide insight into the early steps of protein-mediated biomimetic nucleation of iron oxide and point to the importance of an extended protein surface during nanoparticle formation.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Iron(III) chloride hexahydrate, puriss. p.a., reag. Ph. Eur., ≥99%
Sigma-Aldrich
Iron(III) chloride hexahydrate, reagent grade, ≥98%, chunks
Sigma-Aldrich
Iron(III) chloride hexahydrate, ACS reagent, 97%
Sigma-Aldrich
Iron(III) chloride hexahydrate, puriss. p.a., ACS reagent, crystallized, 98.0-102% (RT)