Dmitry Kopelevich
Ph.D., 2002, University of Notre Dame
Associate Professor
Ph : 352-392-4422
Self-assembled surfactant systems
Stability of biomembranes
Transport through self-assembled membranes
Our research focuses on theoretical and computational investigation of transport phenomena and non-equilibrium processes in nanoscale systems. We apply molecular dynamics and multi-scale simulations, as well as theoretical tools, to various nanoscale systems whose understanding is of significant scientific and technological importance.
Self-assembled surfactant systems

Surfactants (or amphiphiles) are molecules that contain both hydrophobic and hydrophilic segments. In aqueous solutions surfactants spontaneously self-assemble into a variety of microstructures that find use in numerous applications, including drug delivery vehicles and templates for advanced nanostructured materials. In addition to their industrial uses, self-assembled structures of amphiphilic molecules, such as lipid bilayers, are building blocks for various biological systems. In all of these systems, the dynamics of self-assembly and transitions between different self-assembled structures plays an important role. Our goal is to understand molecular mechanisms of these transitions. Currently, we are investigating several systems, including formation and break-up of spherical micelles and dynamics of lipid membranes.

Stability of biomembranes

One of common causes of cell death is disruption of the cellular membrane. Therefore, understanding mechanisms of the membrane instability is important in various biomedical applications. For example, improvement of antimicrobial agents (e.g., peptides) which efficiently kill bacteria by destabilizing their membranes may lead to development of medications which do not promote antibiotic resistant strains of bacteria. On the other hand, reduction of toxicity of various industrial products calls for development of materials which do not destabilize cellular membranes on contact. Our current research is focused on investigation of stability of the major constituent of cellular membranes (lipid bilayers) to perturbations created by manufactured nanoparticles (such as fullerenes and carbon nanotubes) and surfactant molecules.

Transport through self-assembled membranes

The process of mass transfer across surfactant-covered microemulsion interfaces and lipid bilayers plays an important role in numerous applications, including separations, reactions, drug delivery, and detoxification. We investigate the molecular mechanisms of solute transport across an interface composed of tightly packed amphiphilic molecules and assess various factors that affect this transport.

Recent Publications
1. Ahn, Y. N., Gupta, A., Chauhan, A., and Kopelevich, D. I. “Molecular transport through surfactant-covered oil-water interfaces: Role of physical properties of solutes and surfactants in creating energy barriers for transport”, Langmuir 27 (2011), 2420-2436.
2. Gupta, A., Chauhan, A. and Kopelevich, D. I. “Molecular Transport across Fluid Interfaces: Coupling between Solute Dynamics and Interface Fluctuations”, Phys. Rev. E 78 (2008), 041605.
3. Chen, C.-Y. and Kopelevich, D.I., “Phonon Interactions in Zeolites Mediated by Anharmonicity and Adsorbed Molecules,” Mol. Simulat., 34 (2008) 155.
4. Mohan, G. and Kopelevich, D.I., “A Multi-Scale Model for Kinetics of Formation and Disintegration of Spherical Micelles,” J. Chem. Phys., 128 (2008) 044905.
5. May, E.R., Narang, A. and Kopelevich, D.I., “Role of Molecular Tilt in Thermal Fluctuations of Lipid Membranes,” Phys. Rev. E, 76 (2007) 021913.