Maria Stepanova, PhD, DrSci, PEng

Area of Study / Keywords

Biomedical Engineering Microsystems and Nanodevices Photonics and Plasmas Nanofabrication Electron Beam Lithography

About

Dr.Sci. (Physics and Mathematics) Higher Attestation Commission, Moscow, 1998

Ph.D. (Physics and Mathematics) National Center for Surface and Vacuum Research, Moscow, 1992

M.Sc. (Physics) Lomonosov Moscow State University, 1984

Research

Development, fabrication, and characterization of bio-nano-electro-mechanical systems for multifunctional applications

Bio-nano-electro-mechanical systems (bio-NEMS) interfacing stimuli responsive biological polymers with solid state electronic devices are expected to revolutionize emerging technologies in the coming decades. Multifunctional materials and devices for precision biomedical diagnostics, modulation of stimuli-responsive materials, or green energy harvesting are examples of the applications. In our team, we develop an experimental platform for fabrication, characterization and modulation of such conjugate nano-biological architectures. In particular, we want to be able inducing and detecting inter-molecular binding, conformation/morphology changes, and electron transfer events in biological polymers confined on solid nanostructured surfaces. Our designs include protein or aptamer molecules immobilized on nanostructured surfaces in solution, in particular allowing for ultra-sensitive surface-enhanced Raman spectroscopy (SERS) detection of these immobilized polymers and their interactions with respective ligands. SERS allows for a capture of unique signatures corresponding to molecular vibrations, making it an unmatched technique for molecule-specific "fingerprinting". Non-limiting applications include development of biosensors for small molecules or peptides in solution.

Ultrahigh resolution nano-lithography

The ability to fabricate structures (plasmonic materials, electrodes, switches, channels, etc.) down to deep nanoscale dimensions with a high size and position control is critical for successful development of bio-nano-electro-mechanical devices. Over the recent years, we have optimized electron beam lithography (EBL) processes to be able fabricating dense arrays of nanostructures, as well as bridge nano-architectures. Building upon these experiences, we are working to develop efficient nanostructured substrates involving dimensions below 15-20 nm for SERS bio-detection and other applications. Complementary to EBL, we are also interested in optimizing and applying focused ion beam (FIB) and nano-imprinting lithography (NIL) techniques in order to increase, respectively, the resolution and throughput of nanofabrication.

Fundamental studies of biopolymers and bio-solid interfaces

Proteins and other bio-polymers are extremely complex systems that change their spatial organization (conformation) when they perform their function, as well as in response to various extrinsic stimuli. When biopolymers are a part of a conjugate nano-biological system, confinement to a device's surface adds even more dimensions to this complexity. Our research relies strongly upon the usage of well-established modeling tools, such as molecular dynamics simulations, statistical-mechanical analysis, and kinetic modeling, as well as our original inventions, such as the essential collective dynamics method, to better understand the structure and dynamics of biopolymer molecules, biological membranes, self-assembled monolayers, and their interactions at bio-solid interfaces.

Teaching

ECE209 (2021,2022)

ECE341 (2020)

ECE202 (2019)

ECE750 "Simulation of Nanostructured Materials” (2007)

PHYS395 "Electronics" (2003,2004)