Types of Materials We Study

Applications of Interest to Us

Self-Assembled Nanostructures

The self-assembly of molecules into nanostructures is the primary area of expertise for the group. A range of self-assembled structures are being studied, including wormlike micelles (long, flexible chains of surfactants), vesicles and liposomes (self-assembled containers), helical tubules (folded or wrinkled sheets of lipid molecules), and chromonic liquid crystals (assemblies of aromatic dyes or drugs). The ability to tune self-assembly by external variables such as light, pH or temperature is of particular interest.

Polymers & Biopolymers

Polymeric and biopolymeric fluids and materials are actively being investigated in the group. Polymer nanocomposites based on carbon nanotubes and nanoclays are being studied with a focus on their rheological properties. Biopolymer hydrogels and capsules are being developed in the context of drug delivery and controlled release applications. Also, the synthesis of nanoporous polymers from self-assembled templates is being studied.

Colloids & Nanoparticles

Colloids and nanoparticles are key components in a number of systems under study in the group. In one project, the assembly of clay nanoparticles (e.g., laponite) into nematic liquid crystals in organic media is being investigated. Dispersions and gels of carbon nanotubes are being evaluated with a focus on their rheological properties. Finally, micron-sized capsules with magnetic nanoparticles are being developed for drug delivery applications.

Smart / Tunable Fluids & Gels

Smart fluids or materials, i.e., those whose properties can be tuned by external stimuli, are of particular interest to the group. A project funded by an NSF CAREER award deals with light-sensitive fluids that can switch reversibly from a low to a high viscosity upon irradiation at different wavelengths. Such fluids could be useful in MEMS devices. Vesicle to micelle transitions in response to temperature and pH are also being studied, and these could form the basis for drug delivery systems. Also, thermoreversible gels that shrink upon heating or cooling are being developed with funding from a startup company, Prasidiux Inc. through the MIPS program.

Drug Delivery & Nanomedicine

Colloidal carriers for controlled and targeted drug delivery are an emerging area of interest for the group. Hydrogels containing vesicles are being evaluated for topical delivery in a collaboration with the FDA. Liposomes with gelled cores ("nanogels") are being studied in collaboration with two groups at NIST. Microcapsules with embedded magnetic particles and/or vesicles are being developed for targeted delivery to tumors in a collaboration with the UMD School of Pharmacy.

Advanced Plastics

Advanced polymeric materials with enhanced properties are a focal point for much of the group's work. A project funded by the NIST Building and Fire Research Lab aims to develop strong, fire-retardant plastics by embedding a small amount of carbon nanotubes or clay particles in them. Another project funded by Du Pont seeks to make nanoporous polymers, which could find application as membranes or sensors.

Experimental Techniques that We Use Frequently