E-mail: Alex_Smirnov@ncsu.edu
Phone: (919)-513-4377
FAX: (919)-515-8909
Research activities in the Prof. Smirnov lab are concentrated in three principal areas: 1) lipid nanotube arrays for protein biochips and hybrid nanoscale devices, 2) fundamental roles of intermolecular interactions in self-assembly and structure-function relationships of membrane proteins, 3) coupled spin systems and spin coherence in nanostructures and information devices that are based on quantum principles
1) Lipid Nanotube Arrays
Prof. Smirnov group at NCSU is taking on an alternative approach to building substrate-supported
lipid bilayers and protein biochips. Our methodology is based on the property of phospholipids to
self-assemble inside the nanopores into cylindrical structures we discovered recently. We have
already confirmed the existence of these structures, which we call lipid nanotubes, with spin
labeling Electron Paramagnetic Resonance (EPR) and 31P NMR. Specifically, we determined that
when supported by well-aligned through-film rigid nanopores of Anodic Aluminum Oxide (AAO)
substrate, these lipid nanotubes exhibit an exceptionally high degree of static order while the
other local properties are remarkably similar to those of unsupported membrane vesicles.
Currently, we are utilizing our substrate-supported lipid nanotube technology to develop a new
generation of robust and efficient hybrid nanoscale devices. Specifically, using variety of
spectroscopic approaches, we are characterizing binding of proteins to lipid nanotubes and
optimizing conditions for patterned deposition of lipids and proteins onto nanoporous substrates.
2) Intermolecular Interactions in Self-assembly of Membrane Proteins
Electrostatic interactions and hydrogen bonding play fundamental roles in protein folding and
assembly of proteins in membranes. Despite their fundamental importance, local electrostatic
interactions in proteins and membranes remain to be very elusive parameters because of
the scarcity of the experimental methods that can be used to measure these effects
accurately and unambiguously. In our lab we are using high resolution high field EPR
(HF EPR) and site-specific labeling of biopolymers to map these interactions and protein
side-chain dynamics on atomic level. Currently, using HF EPR, which has a sub-picomolar
quantity protein/peptide requirement, we are mapping local polarity and peptide-membrane
interaction for a series of short model peptides and spin-labeled proteins in order to derive
the relationship between local electrostatic and structural conformation of biopolymers.
The next phase of this work will be focused on studies of electrostatics and molecular
mechanisms of interactions of viral peptides and drugs with lipid bilayers.
3) Spin Coherence in Nanostructures and Quantum Information Devices
Electrical characterization of quantum confinement and spin coherence in nanostructures is
primarily an unchartered area of research and that requires state-of-the-art combination of
cryogenic temperatures, high magnetic fields, and mm-wave low noise techniques. In
collaboration with Profs. Misra, Wook, and Holton (Electrical & Computer Eng., NCSU)),
who are designing and manufacturing quantum dot arrays of a pure silicon design where
the electron is trapped at the Si to SiO2 interface beneath a metal electrode., our
laboratory is engaged in developing of specialized EPR technology to characterize and
to manipulate quantum properties of the electronic spins at cryogenic temperatures.
Glenn_Hennessee@ncsu.edu
