Our research concerns the identification, synthesis, and characterization of polymers with selected functionality, composition, and molecular architecture. Several areas of polymer chemistry are being investigated, with particular focus on those most closely related to biological applications.

  1. Functional polymer synthesis and efficient polymer modification via specific and orthogonal methodologies. A significant effort is dedicated to devising new synthetic routes to functional macromolecules. In addition to relying on living/controlled radical polymerization techniques to prepare polymers of controlled molecular weight and retained end group functionality, highly efficient postpolymerization modification is required to incorporate functionality not easily included in monomer, initiator, or chain transfer agents. Many chemical transformations employed in organic synthesis do not demonstrate the same degree of efficiency and orthogonality when used for functionalization of high molecular weight  macromolecules. Therefore, a significant effort in our group has involved the extension of "click chemistry" methodologies for functional polymer synthesis.

  2. Stimuli-responsive water-soluble block copolymers. The solution behavior of polymers that exhibit "smart" behavior in aqueous media is being investigated. Responsive block copolymers can be induced to form micelles, vesicles, or gels, and may ultimately lead to new applications in controlled drug delivery, tissue engineering, and surface biocompatibilization.

  3. Dynamic-covalent macromolecular materials. By constructing macromolecular assemblies with linkages that are reversibly covalent, we prepare new materials with the ability to adapt their structure, constitution, and reactivity depending on the nature of the surrounding environment. Reversibility being a key attribute, these systems offer versatility typically associated with supramolecular materials (dynamic rearrangement, self-assembly, self-repair, etc.), while maintaining the integrity and robust nature of covalently formed polymers. Materials constructed via covalent bonds that can be triggered to dissociate in response to specific chemical stimuli include smart nanoparticles, organogels, and self-healing coatings.

  4. Smart polymer-protein bioconjugates. Modifying biological molecules with "smart" polymers provides a means to externally control the solubility and activity of proteins, peptides, and nucleic acids. Examples of such hybrid materials include polymer-protein conjugates in which the activity, stability, or solubility of the protein can be tuned by capitalizing on the responsive nature of the immobilized synthetic polymer.