Nicholas A Kotov

Nicholas A. Kotov, FRSC (born August 29, 1965, Moscow, USSR), is the Joseph B. and Florence V. Cejka Professor of Chemical Engineering at the University of Michigan in Ann Arbor, MI. He is best known for his work on the self-assembly of nanoparticles the layer-by-layer assembly (LbL) of composites, and chiral nanostructures.

Contents

• Mrs medal award winners sharon glotzer nicholas a kotov
• Stretchable conductors mconnex michepedia
• Education and early career
• Independent research career
• Professional achievements
• Personal life
• References

The LbL deposition of charged macromolecular species was discovered in 1965 by J. J. Kirkland and R. K. Iler using films of microparticles, and later re-discovered by Gero Decher in 1991 as a versatile deposition method for polyelectrolytes. In his early work, Kotov extended this technique to nanoplatelets of clay, graphene, graphene oxide, and other nanoparticles, which provided a pathway towards the development of ultrastrong materials. Kotov found that these composites replicate the structure and mechanical properties of nacre, which spurred on studies of nanoscale versions of nacre for application in neuroprosthetic devices, tissue engineering, and energy storage. His later studies led to the discovery of nanomaterials based on the Japanese art of kirigami, and plasmonic nanocomposites.

The biomimetic self-organization of nanoparticles is central to Kotov’s work. He discovered that inorganic nanoparticles can spontaneously self-organize into chains, sheets, nanowires, and particulate superlattices. The geometry of these often sophisticated assemblies is determined by the fairly unsophisticated anisotropy of nanoparticle interactions. The diversity and complexity of nanoparticle assemblies approaches that of self-assembled structures of biomolecules, and are rooted in the non-additivity of electrostatic, van der Waals and other classical interactions at the nanoscale. Examples of the intricate self-organized assemblies achievable by nanoparticles include twisted ribbons and virus-like nanohelices. Recently, it was discovered that helical assemblies with near perfect enantiomeric excess can be prepared from D- or L-cysteine stabilized nanoparticles. This is a significant improvement over previous work where two enanotimers co-existed and their corresponding chiroptical properties were difficult to untangle.

Biomimicry of viruses in nanomaterials can also be seen in Kotov’s spherical supraparticles that are self-assembled from several hundred individual nanoparticles, replicating proteins in viral capsids. The supraparticles can be related to micelles and vesicles, exemplifying terminal self-assembled structures. Their size and geometry is determined by the equilibrium state originating from the balance of repulsive and attractive interactions. The generic nature of such interactions allows the preparation of a large variety of supraparticles that may include different organic and inorganic components. The integration of nanoscale and biological components in supraparticles led to the first bionic nanoassemblies that integrated the functions of inorganic and biological components.

The biomimetic functions of inorganic nanoparticles transitioned from laboratory to practice with Kotov’s discovery that pyramidal nanoparticles inhibit the essential bacterial enzyme β-galactosidase. The capacity of these biomimetic nanoparticles to serve as new antibacterial agents against methicillin-resistant Staphylococcus aureus (MRSA) and other antibiotic resistant bacteria addresses a pressing healthcare need.