Research

The Trewyn research group focuses on the design, synthesis, characterization and utility of porous materials in the area of drug delivery, gene delivery to plant cells, heterogeneous catalysis, fuel cells, and separations of challenging metals and analytes. We focus on replacement of precious metals and rare earths in catalysis, developing tandem catalysis systems for valorization of biomolecules, and taking biochemical approaches to load mesopores with large biomolecules. For many projects we investigate biological systems for solutions to catalytic and materials synthesis challenges.

Below is a list of some of the ongoing projects in the Trewyn group:

  • Techniques to Functionalize and Utilize Ordered Mesoporous Carbon for Fuel Cell Applications

Significant efforts have been devoted in the past decade towards the construction of ordered mesoporous carbons (OMCs) as a solid support in the field of heterogeneous catalysis and electrochemistry due to its unique properties such as high surface area, tunable pore size, hydrophobic surface properties, chemical and mechanical stability and high thermal and electrical conductivity. These OMCs have high surface areas (800-1000 m2g-1) and large pore sizes (4-6 nm) suitable for anchoring bulky inorganic complexes. We have introduced and continue to develop a universal and benign approach to covalently anchor functional groups and catalysts on the surface of OMCs based on lithium-mediated chemistry. We demonstrated that this organic porous nanomaterial, when covalently supporting molecular catalysts for C-H bond activating, can be prepared in a fuel cell that oxidizes methane at low temperature.

Universal and Versatile Route for Selective Covalent Tethering of Single-Site Catalysts and Functional Groups on the Surface of Ordered Mesoporous Carbons.

Organometallic Complexes Anchored to Conductive Carbon for Electrocatalytic Oxidation of Methane at Low Temperature

Figure-1_flat Trewyn Research Activities
  • Large Biomolecule Delivery Technology

Mesoporous silica nanoparticles (MSN) have been shown to be excellent materials for the controlled release and drug delivery vehicles for small drug molecules and small biomolecules. We are utilizing both material synthesis and biochemistry techniques to entrap large proteins and enzymes in the pores of MSN materials by dissociating large multisubunit proteins into units small enough to load into the mesopores. Upon release into an appropriate environment, the subunits reassociate and form an active protein.

Controlled Release and Intracellular Protein Delivery from Mesoporous Silica Nanoparticles

Conserved Activity of Reassociated Homotetrameric Protein Subunits Released from Mesoporous Silica Nanoparticles

Figure-3_flat Trewyn Research Activities
  • Tandem Heterogeneous Catalysis

Through a combination of catalytic species, a tandem process provides structurally advanced products from relatively simple substrates without the need for isolation of the intermediates. One of the obstacles is identifying multiple reactions that can occur in a cascade in a single reaction environment or to develop a material with a versatile morphology that can host multiple local environments. The unique porous morphology of inorganic mesoporous materials (MSN) make these applications possible with the ability to utilize the pore framework as a confined, distinct space (environment) to encapsulate drug molecules or tether and immobilize inorganic active catalytic sites.

Aerobic oxidative esterification of primary alcohols over Pd-Au bimetallic catalysts supported on mesoporous silica nanoparticles

Figure-4_flat Trewyn Research Activities
  • Functionalization of Porous Inorganic Nanomaterial for Chemical, Protein, and Gene Delivery for Plant Cells

The cell wall on most plant cells and many microalgae present a unique challenge to deliver small and large biologically active molecules. Utilizing “Gene Bombardment”, a technique developed in the mid 1980s, researchers have been able to deliver genomic material to plant cells by biolistics using solid gold particles as delivery vehicles. We have made advances to this technology by giving density to our mesoporous silica nanoparticles by incorporating nanoparticle gold either as caps or as surface modifiers. We have shown for the first time that chemicals and enzymes can be delivered along with DNA to tobacco, maize, and onion cells. This work is in collaboration with Prof. Kan Wang of Iowa State University.

Mesoporous Silica Nanoparticles Deliver DNA and Chemicals into Plants.

Gold Functionalized Mesoporous Silica Nanoparticle Mediated Protein and DNA Codelivery to Plant Cells Via the Biolistic Method

Mesoporous Silica Nanoparticle-Mediated Intracellular Cre Protein Delivery for Maize Genome Editing via loxP Site Excision

Figure-2_flat Trewyn Research Activities