Synthesis of Triangular Silver and Gold Nanoprisms Using Consensus Sequence Tetratricopeptide Repeat Proteins

Area of Science:

• Nanotechnology and Materials Science
• Plasmonics and Nanophotonics
• Biomolecular Engineering

Background:

• Anisotropic metallic nanoparticles, including gold (Au) and silver (Ag) nanoprisms (NPSMs), are crucial for diverse applications like catalysis, sensing, and bioimaging.
• Their utility stems from unique shape-dependent optical and physical characteristics, driving demand for controlled synthesis methods.
• Existing synthesis routes often struggle with achieving low polydispersity and narrow size distributions.

Purpose of the Study:

• To present a novel protein-enabled synthetic strategy for producing anisotropic silver and gold nanoprisms (NPSMs).
• To achieve high control over nanoparticle shape, size distribution, and plasmonic absorbance.
• To utilize specific proteins as stabilizers for enhanced seed nucleation and growth.

Main Methods:

• Employed consensus sequence tetratricopeptide repeat (CTPR) proteins as stabilizers during the initial seed nucleation phase.
• Facilitated the formation of planar-twinned silver (Ag) seeds using CTPR.
• Achieved seeded growth of well-defined Ag/Au NPSMs by introducing CTPR-stabilized Ag seeds into a growth solution containing metal precursors, a mild reducing agent, and sodium halide.

Main Results:

• Successfully synthesized anisotropic silver and gold nanoprisms (NPSMs) with low shape polydispersity and narrow size distribution.
• Demonstrated tailored plasmonic absorbance properties through controlled nanoparticle synthesis.
• Achieved high yield production of well-defined Ag/Au NPSMs using the protein-stabilized seeded growth approach.

Conclusions:

• The protein-enabled strategy offers a robust and efficient method for synthesizing high-quality anisotropic metallic nanoparticles.
• CTPR proteins are effective stabilizers for controlling seed formation and subsequent nanoprism growth.
• This approach provides a pathway for developing advanced nanomaterials with precisely engineered optical properties for various scientific and technological fields.