Shelby Taylor

Advances toward bioapplications of carbon nanotubes

Bioapplications of carbon nanotubes have been predicted and explored ever since the discovery of these one-dimensional carbon allotropes. Indeed, carbon nanotubes have many interesting and unique properties potentially useful in a variety of biological and biomedical systems and devices. Significant progress has been made in the effort to overcome some of the fundamental and technical barriers toward bioapplications, especially on issues concerning the aqueous solubility and biocompatibility of carbon nanotubes and on the design and fabrication of prototype biosensors. In this article we take a comprehensive look at the advances in this fast-moving and exciting research field. We review the current status of available methodologies for the aqueous dispersion and solubilization of carbon nanotubes, discuss the results on modifications of carbon nanotubes with various biological and bioactive species, and highlight some of the recent achievements in the fabrication and evaluation of carbon nanotube-based bioanalytical devices.

Immuno-carbon nanotubes and recognition of pathogens.

Carbon nanotubes have been widely investigated for their unique combination of properties including their one-dimensional hollow structure, high-strength with flexibility, large surface area, and chemical stability. 2] There has also been growing interest in their potential biological applications, especially in biosensors and vaccineand drug-delivery systems. 4] Both singleand multiple-walled carbon nanotubes (SWNT and MWNT, respectively) can be modified and conjugated with bioactive molecules and biological species including carbohydrates, 6] amino acids and peptides, nucleic acids and analogues, and proteins. We have previously demonstrated that SWNTs are naturally protein affinitive in water and that covalent modification of the nanotubes with proteins gives stable conjugation and excellent aqueous solubility of the conjugates. Here we report the preparation of immuno-carbon nanotubes by conjugating pathogen-specific antibodies to the SWNTs that are functionalized with bovine serum albumin (BSA) protein (Scheme 1) and, for the first time, the recognition of target pathogen cells by the immuno-carbon nanotubes via antibody–antigen interactions in physiological environment.

Luminescence anisotropy of functionalized carbon nanotubes in solution

Luminescence anisotropy of functionalized single-wall (SWNT) and multiple-wall (MWNT) carbon nanotubes in solution and in polymeric thin-film matrix was investigated. The results show that the absorption and emission dipole moments are intrinsically collinear, corresponding to the limiting positive anisotropy. The observation of strong luminescence polarization for the functionalized carbon nanotubes in room-temperature chloroform is consistent with the polymeric nature of these luminescent species; and the partial depolarization in solution is rationalized in terms of the flexibility of the nanotubes.

RESS for the preparation of fluorinated porphyrin nanoparticles

Rapid Expansion of Supercritical Solutions (RESS) was used to produce clean, surfactant-free nanoparticles (average size = 60 nm) of a fluorinated tetraphenylporphyrin from supercritical solutions with CO2.