Context <p>Single-walled carbon nanotubes (SWCNTs) are promising platforms for biosensing because their electronic properties are sensitive to molecular adsorption. While canonical nucleic acid bases have been extensively studied, little is known about how synthetic Hachimoji bases interact with nanotube surfaces. In this study, we investigate the adsorption of uridine (rU) and the Hachimoji base S (rS) on a finite (5,5) SWCNT fragment. The study aims to compare binding strength and electronic effects between canonical and synthetic bases within a finite gas-phase SWCNT model and to examine whether the two bases show distinguishable local adsorption behavior.</p> Methods <p>All geometries of the isolated molecules and the SWCNT+rU and SWCNT+rS complexes were fully optimized using density functional theory (DFT) with the PBEh-3c composite method in ORCA. The adsorption complexes were analyzed on an 8&#xa0;Å hydrogen-terminated (5,5) SWCNT fragment, with the bases initially placed approximately parallel to the nanotube sidewall at ~ 3.1&#xa0;Å. HOMO-LUMO gaps were calculated for each system: rU (~ 7.5&#xa0;eV), rS (~ 7.7&#xa0;eV), SWCNT (~ 3.21&#xa0;eV), SWCNT + rU (~ 3.19&#xa0;eV), and SWCNT + rS (~ 3.20&#xa0;eV). Interaction energies of the optimized complexes were computed using the supermolecule approach, yielding − 0.43364&#xa0;eV for SWCNT+rU and − 0.55405&#xa0;eV for SWCNT + rS. Mulliken population analysis was performed to quantify fragment charge redistribution, showing only minor net charge transfer.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Comparative investigation of uridine and Hachimoji RNA base interaction with single-walled carbon nanotube

  • Mashari Alangari

摘要

Context

Single-walled carbon nanotubes (SWCNTs) are promising platforms for biosensing because their electronic properties are sensitive to molecular adsorption. While canonical nucleic acid bases have been extensively studied, little is known about how synthetic Hachimoji bases interact with nanotube surfaces. In this study, we investigate the adsorption of uridine (rU) and the Hachimoji base S (rS) on a finite (5,5) SWCNT fragment. The study aims to compare binding strength and electronic effects between canonical and synthetic bases within a finite gas-phase SWCNT model and to examine whether the two bases show distinguishable local adsorption behavior.

Methods

All geometries of the isolated molecules and the SWCNT+rU and SWCNT+rS complexes were fully optimized using density functional theory (DFT) with the PBEh-3c composite method in ORCA. The adsorption complexes were analyzed on an 8 Å hydrogen-terminated (5,5) SWCNT fragment, with the bases initially placed approximately parallel to the nanotube sidewall at ~ 3.1 Å. HOMO-LUMO gaps were calculated for each system: rU (~ 7.5 eV), rS (~ 7.7 eV), SWCNT (~ 3.21 eV), SWCNT + rU (~ 3.19 eV), and SWCNT + rS (~ 3.20 eV). Interaction energies of the optimized complexes were computed using the supermolecule approach, yielding − 0.43364 eV for SWCNT+rU and − 0.55405 eV for SWCNT + rS. Mulliken population analysis was performed to quantify fragment charge redistribution, showing only minor net charge transfer.