Eugenia Kumacheva's Polymers, Interfaces, and Materials Science Group

Nanoscience

1. Developing new concepts for nanoparticle self-assembly                                           

Our group is interested in developing new strategies for the self-assembly of hierarchically organized nanostructures with a high degree of order and symmetry, ­and exploring their collective properties. One of our approaches stems from the analogy between molecules undergoing a chemical reaction and nanoparticles which, when cleverly designed, behave as "colloidal molecules'. This work includes the synthesis of nanoparticles with different dimensions, shapes and compositions, the design and synthesis of ligands (in most cases, polymers), nanoparticle patterning with surface "patches", the self-assembly experiments, and the characterization of the structure and properties of nanoparticles and their ensembles.

We are also interested in bioinspired self-organization of nature-derived nanoparticles in liquid crystals.  This type of nanostructures is often responsible for brilliant and iridescent colors in the animal and plant kingdom.  We also use colloidal liquid crystals as hosts and templates for other types of nanoparticles and target their interesting and practically useful optical applications. One of the fundamentally interesting directions in this area of research is self-assembly of nanoparticles in confinement.

Representative publications

· Li, Y.  Periodic Assembly of Nanoparticle Arrays in Disclinations of Cholesteric Liquid Crystals. Proc. Nat. Acad. Sci. U.S.A., 114, 2137–2142 (2017).

· Li, Y. et al. Colloidal Cholesteric Liquid Crystal in Spherical Confinement. Nature Comm. 7, 12520 (2016).

· Klinkova et al.  Structural and Optical Properties of Self-Assembled Chains of Plasmonic Nanocubes. Nano Lett. 14, 6314-6321 (2014).

·         Liu et al.   Copolymerization of Metal Nanoparticles: A Route to Colloidal Plasmonic Copolymers.  Angew. Chem. Int. Ed. 53, 2648-2653 (2014).

·         Klinkova et al. Colloidal Analogues of Molecular Chain Stoppers. Proc. Nat. Acad. Sci. 110, 18775-18779 (2013).

·         Liu et al.  In Situ Plasmonic Counter for Polymerization of Chains of Gold Nanorods in Solution. ACS Nano 7, 5901-5910 (2013).

·         Lee et al.  Probing Dynamic Generation of Hot-Spots in Self-Assembled Chains of Gold Nanorods by SERS.  J. Am. Chem. Soc.133, 7563-7570 (2011).

·         Liu et al. Step-Growth Polymerization of Inorganic Nanoparticles. Science 329, 197-200 (2010).

·         Nie, et al. 'Supramolecular' Assembly of Gold Nanorods End-Terminated with Polymer 'Pom-Poms': Effect of 'Pom-Pom' Structure on the Association Modes. J. Am. Chem. Soc. 130, 3683-3689 (2008).

·         Nie, Z et al. Self-assembly of Metal-Polymer Analogues of Amphiphilic Triblock Copolymers. Nature Mater. 6, 609-614 (2007).

2. Nanoparticle patterning                                             

We explore the structure and function of polymer molecules grafted to inorganic nanoparticles. By controlling the composition and configuration of end-grafted polymer ligands, we induce their precisely controllable organization in surface “patches’. Patchy nanoparticles act as “colloidal molecules” and have interesting fundamental properties and promising applications in nanoscience.  We are interested in new polymer ligands, new properties of “patchy” nanoparticles”, their applications in nanomedicine, and new modes of self-assembly of these nanoparticles in nanomaterials with advanced properties. This area of research is cross-listed with our research in the Polymer area.

Representative publications

·         Choueiri,, R.M. et al.Self-assembly and surface patterning of polyferrocenylsilane-functionalized gold nanoparticles. Macromol. Rapid Comm. 39, 1700554 (2018).

·         Tebbe, M. et a. Homopolymer Nanolithography. Small 13, 1702043 (2017).

·         Galati, E. et al. Shape-specific patterning of polymer-functionalized nanoparticles.  ACS Nano 23, 4995-5002 (2017). 

·         Choueiri,  R.M. et al. Surface patterning of nanoparticles with polymer patches. Nature 538, 79-83 (2016).

3. Nanoparticles derived from natural resources

We are developing new materials derived from nature-derived nanoparticles. In one project, we use cellulose nanocrystals to create biomimetic hydrogels for applications in biology and tissue engineering. In another project, we synthesize and fabricate composite nanostructured materials with advanced optical and mechanical properties.  In the third project, we use them to design and develop nanocolloidal hydrogels for heavy metal scavenging.

Representative publications

·       Alizadehgiashi, M. et al. Nanocolloidal Hydrogel for Heavy Metal Scavenging. ACS Nano (accepted).

·       Alizadehgiashi, M. et al. Shear-induced alignement of anisotropic nanoparticles in a single-droplet oscillatory microfluidic platform. Langmuir 34, 322-330 (2018). Cover page.

·       Vollick, B. et al. Composite Cholesteric Nanocellulose Films with Enhanced Mechanical Properties. Chem. Mater. 29, 789–795 (2017).

·        Thérien-Aubin et al. Structure and Properties of Composite Films Formed by Cellulose Nanocrystals and Charged Latex Nanoparticles. Nanoscale 7, 6612-6618 (2015).

·         Chau et al.  Ion-Mediated Gelation of Aqueous Suspensions of Cellulose Nanocrystals. Biomacromolecules 16 , 2455–2462 (2015).

·         Querejeta-Fernández et al. Chiral Plasmonic Films Formed by Gold Nanorods and Cellulose Nanocrystals. J. Am. Chem. Soc. 136, 4788-4793 (2014).