Molecular Recognition Using Carbon Nanotube Adsorbed Polymer and Bio-Polymer Phases: Synthetic Nanotube Templated Antibodies

Molecular recognition is central to the design of chemical catalysis and sensor platforms. By far the most common mechanisms involve biological structures such as antibodies1 and aptamers3. This research project proposes the development of new generic molecular recognition sites whereby a synthetic heteropolymer is constrained in space by adsorbing and pinning it to a cylindrical nanotube surface. The use of a nanoparticle substrate to control the structure of an adsorbed polymer to enable molecular recognition of an analyte has thus far been unexplored in the literature to date. Note that this approach requires no templating a priori of the analyte. Instead of intermolecular forces that shape and pin the polymer in 3D space, the nanotube scaffold confines the adsorbed polymer to a cylindrical geometry. We have shown that such polymer-nanotube complexes can reveal highly specific recognition for seemingly unrelated molecules such as riboflavin, dopamine, and others. The binding constants can be made to span more than four orders of magnitude by changing the chemical structure of the heteropolymer. To date, biological pathogens or threats have raised extensive concern to civilians and military personnel. Recent research has found that glycan containing biological entities such as Anthrax and Tularemia bacterium can be traced using sensing containing carbohydrate binding domains.4 One goal of the project is to develop Synthetic Nanotube- Templated Antibodies (SNTA) to detect and quantify specific glycans on potential biological threats, and measure the binding affinity between glycans and carbohydrate binding domains. The sensing technique would not only provide a high-frequency and label free detection techniques for determining pathogens, but also provide valuable information regarding the nature of the binding and biological attack. As models for small molecular recognition, we will examine the recognition of nitroaromatic species and their derivatives, with preliminary data demonstrating that we can detect several species in this important class.