Adam D. Lazareck

Carbon nanotube probes for single-cell experimentation and assays

Integrating nanotechnology with experimental biology is paramount to advancing fundamental biological science and technology, and, therefore, of high current interest and importance. In this article, we report on a new possibility of utilizing carbon nanotube probes assembled by a modified dielectrophoretic based technique for single-cell experimentation and delivery. The modified approach permits highly reproducible construction of water-stable, highly-aligned, and electrically-conductive probes several hundred microns in length, which hold a great promise for enhancing previously developed molecular-scale intracellular experimental techniques. The results of this work, in particular, indicate that the minimally invasive nanotube probes could be advantageous for studies involving permeabilization and subsequent desorption of molecules into a cell’s interior, thereby obviating permeabilization and diffusion across membranes.

DNA-directed synthesis of zinc oxide nanowires on carbon nanotube tips

This paper describes a class of three component hybrid nanowires templated by DNA directed self-assembly. Through the modification of carbon nanotube (CNT) termini with synthetic DNA oligonucleotides, gold nanoparticles are delivered, via DNA hybridization, to CNT tips that then serve as growth sites for zinc oxide (ZnO) nanowires. The structures we have generated using DNA templating represent an advance toward building higher order sequenced one dimensional nanostructures with rational control.

Detection of nano-confined DNA using surface-plasmon enhanced fluorescence

Surface-plasmon resonance (SPR)-induced enhanced fluorescence was used to detect the presence of fluorescent TOTO-1 bis-intercalated lambda-DNA complexes introduced into a periodic nanopore array. As we show, the proposed technique allows a high detection sensitivity by providing a strong fluorescence-signal efficiency from nano-confined fluorescent complexes. This novel platform could be used for sensing applications, or to detect and investigate the unique behaviors of nano-confined molecular systems.

Optoelectrical characteristics of individual zinc oxide nanorods grown by DNA directed assembly on vertically aligned carbon nanotube tips

The authors describe the properties of electronically active nanowires that can be assembled via DNA directed growth on a nanostructured array. DNA-modified nanoparticles are used to site-specifically address the tips of vertically aligned carbon nanotubes (CNTs) that serve as catalysts for the growth of zinc oxide (ZnO) nanorods. Using conductive probe atomic force microscopy, they measured the conductance characteristics of single ZnO-CNT structures under various force and illumination conditions and at different sites in a large array, thereby establishing that DNA directed formation of multimaterial, optically active nanostructures can yield devices that are electronically functional at the nanometer scale. The inherent ability of DNA to carry and convey encoded information provides the basis for targeted synthesis of nanostructured devices.

Coordinated Nanobiosensors for Enhanced Detection: Integration of Three Dimensional Structures to Toxicological Applications

Joanne I. Yeh, Shoucheng Du, Tian Xia, Adam Lazareck, Jin-Ho Kim, Jimmy Xu, and Andre E. Nel Department of Structural Biology, University of Pittsburgh Medical School; Pittsburgh, PA 15260; Division of Clinical Immunology and Allergy, Department of Medicine, University of California, Los Angeles, CA 90095; # Division of Engineering, Brown University, Providence, RI 02912; Department of Bioengineering; 3501 5 Avenue, Pittsburgh, PA 15260. .