Gold nanoparticle capture within protein crystal scaffolds

Area of Science:

• Biomaterials science
• Nanotechnology
• Crystallography

Background:

• DNA assemblies have been utilized for organizing inorganic nanoparticles into 3D arrays.
• Emergent properties in nanoparticle arrays depend on spacing and geometry.

Purpose of the Study:

• To explore engineered protein crystals as a novel method for biologically mediated assembly of inorganic nanoparticles.
• To investigate the capture and release mechanism of nanoparticles within protein crystals.

Main Methods:

• Utilized engineered protein crystals with 13 nm pores and interior hexahistidine sequences.
• Captured Au25(glutathione)∼17 (nitrilotriacetic acid)∼1 nanoclusters via Ni(ii) coordination.
• Validated nanoparticle loading using confocal microscopy and elemental analysis.
• Confirmed protein crystal integrity post-assembly using single crystal X-ray crystallography.

Main Results:

• Successfully demonstrated the capture of gold nanoclusters within protein crystal pores.
• Validated nanoparticle loading and confirmed the specific protein-nanoparticle interaction.
• Showcased the release of nanoparticles upon exposure to EDTA, which chelates Ni(ii).

Conclusions:

• Engineered protein crystals provide an effective alternative to DNA assemblies for inorganic nanoparticle organization.
• This method allows for controlled nanoparticle loading and release, enabling tunable nanomaterial properties.
• The findings open avenues for developing advanced functional nanomaterials with tailored architectures.