The first oligomer has a higher

The first oligomer has a higher GDC-0973 mw Sepantronium concentration energy of binding with the tube than the flexible one (325 kcal/mol vs 250 kcal/mol). After 50-ns modeling of spontaneous adsorption of r(C)25 onto the nanotube (at 343 K), 19 cytosines (from 25) were stacked with the nanotube surface. Figure 4 Snapshot of r(I) 10 and r(C) 25 adsorbed to SWNT (16,0). (a) In the initial simulation step and (b) after 50-ns simulation. Water molecules and Na+ counterions were removed for better visualization. The sugar-phosphate backbone of r(C)25 and

r(I)10 is shown by red and blue strip, respectively. After r(C)25 adsorption, the complementary oligomer r(I)10 was located near the hybrid prepared and then the system was modeled for the next 50 ns. To accelerate the hybridization process, r(I)10 was moved to r(C)25 NT from the side of one of its ends (Figure  4). The starting structure of r(I)10 was ordered in A-form.

Upon simulation, this oligomer approaches the nanotube and interacts both with the nanotube surface and with r(C)25. The dynamics of interactions between components can be observed in Figure  5 which demonstrates changes in the interaction energy between different components of the system with time. Figure 5 Changes in the interaction energy. Dependence of interaction energy between r(I)10 and Ilomastat r(C)25 adsorbed to SWNT (black), (rI)10 and SWNT (red) on simulation time at 343 K. Arrows indicate the appearance of stacked and H-bonded dimers. At first, we consider changes in the energy of interactions between r(I)10 and SWNT surface (Figure  5). A notable energy increment takes

place after 5 ns of simulation when the oligomer approaches the nanotube and two or three bases (hypoxanthines) are adsorbed on its surface. At the same time, the binding energy of components of the complex reaches approximately 32 kcal/mol. The next energy growth (up to about 60 kcal/mol) takes place after 15 ns when the whole oligomer comes nearer to the nanotube, and this chain is placed practically transversely to the nanotube Tolmetin axis. However, the further simulation does not result in the increase of this energy value. It should be noted that r(I)10 oligomer moving along the tube is prevented by r(C)25 adsorbed earlier onto the nanotube, the conformation of which changes insignificantly with time. Now we consider how the energy of the interaction between two oligomers depends on simulation time (Figure  5). First of all, we note the wide range of fluctuations in the interaction energy. Already at the beginning of simulation, the interaction energy reaches about 30 kcal/mol for a short time (<1 ns), and then the energy varies in the range of 10 to 30 kcal/mol with time.

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