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Full-Text Articles in Engineering
Porphyrin Interaction With Dna-Based Carbon Nanotubes And Regeneration For Light Harvesting, Sawyer E. Morgan, Hanyu Zhang, Jong Hyun Choi
Porphyrin Interaction With Dna-Based Carbon Nanotubes And Regeneration For Light Harvesting, Sawyer E. Morgan, Hanyu Zhang, Jong Hyun Choi
The Summer Undergraduate Research Fellowship (SURF) Symposium
Limitations to current solar cells include the high cost of pure silicon and poor current transfer within cells. An emerging alternative is single-walled carbon nanotubes (SWCNTs), which when combined with DNA and porphyrin chromophores can generate a current when absorbing light. We sought to find a chromophore and conditions that would promote bonding to the SWCNTs and improve light harvesting, while being able to regenerate on the film after being damaged. This was experimentally tested by first making SWCNT films on conducting glass slides. These were then functionalized in solutions of chromophore and spectra were measured to determine the bonding …
Functionalization And Length Fractionation Of Single-Wall Carbon Nanotubes, Nina A. Bragg, Jing Pan, Jong Hyun Choi
Functionalization And Length Fractionation Of Single-Wall Carbon Nanotubes, Nina A. Bragg, Jing Pan, Jong Hyun Choi
The Summer Undergraduate Research Fellowship (SURF) Symposium
Single-wall carbon nanotubes (SWCNTs) are a promising material for future biological applications such as imaging and targeted drug delivery. SWCNTs can be made soluble in water through surface functionalization, a priority for their use in biology. By studying the surface chemistry of SWCNTs, various functionalization methods can be accomplished without perturbing their electronic structure. This study probes the use of pyrene derivatives and phospholipids to non-covalently functionalize SWCNTs, maintaining useful surface properties. Phospholipids cross-linked to polyethylene glycol (PEG) or 1-pyrenebutyric acid conjugated to DNA is anchored onto the sidewalls of SWCNTs by hydrophobic interactions or π-stacking. The PEG/DNA portion is …
Efficiently Dispersing Carbon Nanotubes In Polyphenylene Sulfide, Kevin M. Sommer, R. Byron Pipes
Efficiently Dispersing Carbon Nanotubes In Polyphenylene Sulfide, Kevin M. Sommer, R. Byron Pipes
The Summer Undergraduate Research Fellowship (SURF) Symposium
Thermal plastics are replacing conventional metals in the aerospace, sporting, electronics, and other industries. Thermal plastics are able to withstand relatively high temperatures, have good fatigue properties, and are lighter than metals. Unfortunately, they are not very electrically conductive. However, adding carbon nanotubes to thermal plastics such as polyphenylene sulfide (PPS) can drastically increase the plastic's conductivity at a low weight percent of nanotubes called the percolation threshold. The percolation threshold is the point where adding a little more carbon nanotubes brings together the network of nanotubes and greatly increases the conductivity. We need to learn how to increase the …
Dna Based Carbon Nanotube Porphyrin Nanohybrids Molecular Recognization And Regeneration, Molly M. Riccitelli, Hanyu Zhang, Jong Hyun Choi
Dna Based Carbon Nanotube Porphyrin Nanohybrids Molecular Recognization And Regeneration, Molly M. Riccitelli, Hanyu Zhang, Jong Hyun Choi
The Summer Undergraduate Research Fellowship (SURF) Symposium
In the search to improve solar cells, scientists are exploring new materials that will provide better current transfer. One material that has emerged as a strong contender is the single walled carbon nanotube (SWNT). Current DNA-SWNT based films combined with chromophores have poor operational lifetimes compared to commercial solar cells. Once exposed to light the chromophore begins to degrade, eventually rendering the solar cell unusable. To solve this problem, we used a method involving multiple steps. First we found which DNA sequences formed structures around the SWNT that could hold the most chromophores by using a spectrophotometer to test the …
Synthesis And Characterization Of Nucleic Acid-Functionalized Nanomaterials, Brianna S. Carroll, Jong Hyun Choi
Synthesis And Characterization Of Nucleic Acid-Functionalized Nanomaterials, Brianna S. Carroll, Jong Hyun Choi
The Summer Undergraduate Research Fellowship (SURF) Symposium
Motor proteins such as kinesin move along microtubules in order to transport cellular cargos throughout the cell by obtaining energy from RNA hydrolysis which allows the cell to complete the tasks needed to stay alive. In this work, we developed synthetic molecular motors using DNA enzymes (DNAzyme) and fluorescent nanomaterials which mimic the functions and structures of motor proteins. A DNAzyme-capped CdS nanoparticle and a RNA-functionalized single-walled carbon nanotube (SWCNT) were used as a walker and a track in the motor platform, respectively. As a walking mechanism, the DNAzyme cleaved the RNA substrates in the presence of metal cations. The …