Published on Wednesday March 21, 2007
Two papers published in Nanotechnology and Applied Physics Letters by Dr. Yury Gogotsi, director of the A.J. Drexel Nanotechnology Institute and professor of the Department of Materials Science and Engineering, and colleagues, were featured in a Nanowerk.com story posted on March 16, 2007.
Dr. Gogotsi was quoted in the article and explained that colleagues Dr. Gary Friedman (ECE) and Dr. Adam Fontecchio (ECE) worked with him to assemble nanotubes into nanotube-tipped cellular probes. The article also notes that PhD students in Dr. Gogotsi’s group, Davide Mattia (MSE), Guzeliya Korneva (CHEM; advisor: Yury Gogotsi), and Joshua Freedman (ECE) contributed greatly to the research that was detailed in the two papers.
In “Magnetically assembled carbon nanotube tipped pipettes,” published in Applied Physics Letters, the authors developed a biological probe at the nanoscale with a magnetic carbon nanotube mCNT tip that has the ability to transfer fluids. Fabrication is performed by injection of mCNTs into micropipettes, which are then positioned as probe tips via magnetophoresis, and affixed with polymeric adhesive. The authors discuss the magnetic fabrication process and demonstrate the versatility of this probe (Applied Physics Letters 90, (2007) 103108).
“Multifunctional carbon nanotubes with nanoparticles embedded in their walls,” published in Nanotechnology, describes how the magnetic nanotues for pipettes were made. Controlled amounts of nanoparticles ranging in size and composition were embedded in the walls of carbon nanotubes during a template-assisted chemical vapour deposition (CVD) process. The encapsulation of gold nanoparticles enabled surface enhanced Raman spectroscopy (SERS) detection of organic molecules inside the cavity of the nanotubes. Iron oxide particles are partially reduced to metallic iron during the CVD process giving the nanotubes ferromagnetic behaviour. At high nanoparticle concentrations, particle agglomerates can form. These agglomerates or larger particles, which are only partially embedded in the walls of the nanotubes, are covered by additional carbon layers inside the hollow cavity of the tube producing hillocks inside the nanotubes, with sizes comparable to the bore of the tube, and transforming nanotubes into nanoscale mixers (Nanotechnology 18 (2007) 155305 (7pp).
According to the Nanowerk story, Dr. Gogotsi and colleagues’ research “paves the way to using carbon nanotubes as nanoscale biological probes for sub-cellular investigation.”