טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentKomarov Olga
SubjectCoarse-Grained Monte Carlo Simulation of ssDNA Adsorption
on Carbon Nanotubes
DepartmentDepartment of Chemical Engineering
Supervisor Professor Simcha Srebnik
Full Thesis textFull thesis text - English Version


Abstract

Single-walled carbon nanotubes (SWCNTs) have extraordinary properties due to their symmetry, high aspect ratio, and thermal conductivity, all of which make them attractive towards many applications in medicine, nanotechnology, electronics, optics, and other fields. ssDNA is known to form stable dispersions, and, depending on the sequence of ssDNA, can remarkably enable separation of SWCNTs of a particular chirality. In this work, we use a coarse-grained simulation model to explore the sequence-dependent interaction of ssDNA with SWCNTs. Oligomeric chains of were investigated. Our simulations reveal a significant difference in the thermodynamic behavior of three investigated oligmeric sequences of guanine (G) and thymine (T). Poly(G) was found to adsorb most readily owing to the strong and stable stacking interactions between its bases and the nanotube surface. On the other hand, the smaller thymine bases allow the poly(T) chains to form stacking interactions between neighboring bases as well as with the nanotube simultaneously. Poly(GT) interacts most weakly with the SWCNT and reveals greater sensitivity towards nanotubes with different radii, in contrast to the homopolymers. The uniqueness of each sequence is attributed to geometric as well as energetic differences between neighboring bases.