Generation of polypeptide-templated gold nanoparticles using ionizing radiation.

Area of Science:

• Materials Science
• Nanotechnology
• Biotechnology

Background:

• Ionizing radiation (γ rays, X-rays) has critical applications in various fields.
• Elastin-like polypeptides (ELPs) are versatile biomaterials.
• Controlling nanoparticle synthesis is crucial for advanced applications.

Purpose of the Study:

• To investigate the use of ionizing radiation and cysteine-containing ELPs (C(n)ELPs) for gold nanoparticle (AuNP) synthesis.
• To explore the influence of radiation dose and C(n)ELP type on AuNP characteristics.
• To assess the potential for developing radiation sensors.

Main Methods:

• Synthesis of gold nanoparticles using gold salt solutions, C(n)ELPs (n=2 or 12), and ionizing radiation.
• Characterization of AuNPs using UV-Vis spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM).
• Control experiments to validate the necessity of each component for AuNP formation.

Main Results:

• Ionizing radiation (>175 Gy) in the presence of C(n)ELPs produced maroon-colored AuNP dispersions (λmax = 520 nm).
• AuNPs exhibited hydrodynamic diameters of 80-150 nm (DLS) with gold cores of 10-20 nm (TEM).
• C2ELPs alone synthesized 1-2 nm AuNPs without radiation, indicating dual synthesis pathways.

Conclusions:

• A facile method for gold nanoparticle synthesis using ionizing radiation and C(n)ELPs was established.
• Nanoparticle size can be controlled by adjusting radiation dose and C(n)ELP type.
• This polypeptide-based system shows promise for the colorimetric detection of ionizing radiation.