Project: Biotemplated Synthesis of Encoded Bi-metallic Nanoparticles
Research Team: Yuehe Lin || Yongsoon Shin || J Wang || B Wright
Cryo-TEM image reconstruction of protein cage in closed conformation induced by low pH and/or high concentration of metal ions, and in a swollen conformation induced by high pH and/or low concentration of metal ions. Swelling at the quasi-threefold axis results in the formation of 2-nm pores. Images of CCMV are from VIPER
To build synthesis capabilities and materials characterization approaches of value to homeland security, this Transformational Materials Science Initiative project focuses on developing novel biotemplating approaches to synthesize bi-metallic nanoparticles using virus (protein cages) templates. As compared with single-component metal particles, bi-metallic particles can have continuously tunable electrochemical and optical properties, providing a new platform for multiplex sensing with increased signal:noise ratio. Although protein cages have been widely investigated for the synthesis of inorganic and metallic nanoparticles, bi-metallic nanoparticles with controlled composition and uniform sizes remain a significant challenge.
Au-Ag nanoparticle alloys are being synthesized in Cowpea chlorotic mottle virus cages as either alloys or core-shell nanoparticle structures. This project focuses on the key issues related to bi-metallic nanoparticle formation; i.e., how solution chemistry and protein chemistry affect the diffusion of the metal ions into the protein cage, and subsequently the reduction of different metal ions. The synthesized nanoparticles will be integrated with specific receptors or probes as labels for developing biosensors and diagnostic imaging platforms.
The sensing platforms can be developed for detecting pathogens or toxins from biological fluids or in vitro or in vivo imaging.
Value of this research: This research will lead to establishing a bio-inspired synthesis platform for preparing encoded multicomponent nanoparticles and a sensing platform based on the novel encoded nanoparticle labels. Expected outcomes of the work also include the following:
- Understanding the diffusion and reduction of different metal ions across and inside protein membranes.
- Developing novel encoded nanoparticles with high stability, uniformity in size and shape, and flexibility of functionalities.
- Using encoded nanoparticles as labels to develop biosensing and bioimaging with enhanced selectivity.
- Designing a highly sensitive microchip-based microelectrode array for pathogen detection.