GRADUATE SEMINAR 2

Abstract

Chiral nanoparticles and assemblies represent a large and rapidly evolving class of biomimetic materials. They change the perception of chirality in chemistry, and they enable the facile synthesis of chemical structures with previously inaccessible complexity and structural sophistication. Chiral nanoparticles also offer novel technological venues for information and biomedical technologies due to 10-1000 times increase in magnitude of polarization rotation compared to classical chiral materials [1,2], which opens new directions for detection and treatment major health problems in the world taking advantage of chiral hedgehog particles and bowtie particles, [3] such as cancer and neurodegenerative diseases.

Chiral nanoparticles and their assemblies display giant circular dichroism due to 107 time increase in dynamic polarizability of the inorganic materials, which enables previously unreacheable levels of detection of single biomolecules, such as peptides and nucleotides present in zeptomolar concentrations. Instead of the binary chirality of, for instance, L- or D-amino acids [1-3], the chiral nanoparticles and their assemblies display a continuum of chiral states Studies from multiple groups indicated that the size, geometry, and composition of chiral nanostructures can be tuned to resonate with a wide range of photon energies from ultraviolet to terahertz.

Further studies of nanostructures with finely controlled degrees of left- and right-handedness enabled capturing and detection of cancer-related exosomes with high specificity [4]. Extension of this technology to early detection of the exosomes related to neurodegenerative diseases is currently in progress. Taking advantage of unified Graph Theoretical (GT) description of proteins and nanoparticles, chiral nanostructures can be engineered similarly to protein assemblies to selectively interact with biological counterparts of a similar scale [5]. The strength and selectivity of their interactions can be varied by nanoparticle geometry, and surface ligands, with subsequent utilization in medicine [6], which can be boosted by the development of GT-based and other scale-dependent chirality descriptors. The latest methodology for utilization of chiral vanadate nanoclusters for controlling dynamics of intracellular actin remodeling in neurons will be demonstrated.

References

[1] W. Chen et al.; Nanoparticle Superstructures Made by Polymerase Chain Reaction: Collective Interactions of Nanoparticles and a New Principle for Chiral Materials. Nano Lett., 2009, 9, 2153–2159.
[2] W.J. Choi, et al, Chiroptical Kirigami Modulators for Terahertz Circular Dichroism Spectroscopy of Biomaterials, Nature Materials, 2019, 18, 820–826.
[3] W. Jiang, et al; Emergence of Complexity in Hierarchically Organized Chiral Particles, Science, 2020, 368, 6491, 642-648.
[3] P. Kumar et al; Photonically Active Bowtie Nanoassemblies with Chirality Continuum, Nature, 2023, 615, 418-424.
[4] Y.T Kang et al, Chiroptical detection and mutation analysis of cancer-associated extracellular vesicles in microfluidic devices with oriented chiral nanoparticles, MATTER, 2024, 7(12), 4373-4389.
[5] M. Cha et al, Unifying Structural Descriptors for Biological and Bioinspired Nanoscale Complexes, Nature Computational Science, 2022, 2, 243–252.
[6] L. Xu, et al; Enantiomer-Dependent Immunological Response of Nanoparticles with Light-Induced Chirality, Nature, 2022, 601, 366–373.