Department of Physics, Saratov State University, 410012 Saratov, Russia.
Laboratory of Physics of Nonlinear Media, Institute of Strength Physics and Materials Science of SB RAS, 2/4 Academichesky Avenue, 634021 Tomsk, Russia.
Int J Mol Sci. 2023 Jan 9;24(2):1296. doi: 10.3390/ijms24021296.
Nitrogen-doped multi-walled carbon nanotubes (N-MWCNTs) are widely used for drug delivery. One of the main challenges is to clarify their interaction with hypoxia-inducible factor 1 alpha (HIF-1α), the lack of which leads to oncological and cardiovascular diseases. In the presented study, N-MWCNTs were synthesized by catalytic chemical vapor deposition and irradiated with argon ions. Their chemical state, local structure, interfaces, Stone-Wales defects, and doping with nitrogen were analyzed by high resolution transmission electron microscopy (HRTEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. Using experimental data, supercells of functionalized N-MWCNTs with an oxygen content of 2.7, 4 and 6 at. % in carboxyl groups were built by quantum chemical methods. Our analysis by the self-consistent charge density functional tight-binding (SCC DFTB) method shows that a key role in the functionalization of CNTs with carboxyl groups belongs to Stone-Wales defects. The results of research in the decoration of CNTs with HIF-1α demonstrate the possibility of wave-diffusion drug delivery. The nature of hybridization and relaxation determines the mechanism of oxygen regulation with HIF-1α molecules, namely, by OH-(OH-C) and OH-(O=C) chemical bonds. The concentration dependence of drug release in the diffusion mode suggests that the best pattern for drug delivery is provided by the tube with a carboxylic oxygen content of 6 at. %.
氮掺杂多壁碳纳米管（N-MWCNTs）被广泛应用于药物输送。其中一个主要挑战是阐明其与缺氧诱导因子 1α（HIF-1α）的相互作用，HIF-1α的缺乏会导致肿瘤和心血管疾病。在本研究中，通过催化化学气相沉积法合成了 N-MWCNTs，并对其进行了氩离子辐照。通过高分辨率透射电子显微镜（HRTEM）、拉曼光谱、X 射线光电子能谱（XPS）和近边 X 射线吸收精细结构（NEXAFS）光谱分析了它们的化学状态、局部结构、界面、Stone-Wales 缺陷和氮掺杂。利用实验数据，通过量子化学方法构建了含氧量为 2.7、4 和 6 个原子百分比的含氧官能化 N-MWCNTs 的超晶胞。我们使用自洽电荷密度泛函紧束缚（SCC DFTB）方法的分析表明，Stone-Wales 缺陷在 CNTs 羧基官能化中起着关键作用。用 HIF-1α对 CNTs 进行修饰的研究结果表明了波扩散药物输送的可能性。杂化和弛豫的性质决定了与 HIF-1α分子的氧调节机制，即通过 OH-(OH-C)和 OH-(O=C)化学键。扩散模式下药物释放的浓度依赖性表明，提供最佳药物输送模式的是羧酸氧含量为 6 个原子百分比的管。
