Understanding Non-covalent Interactions in Carbon-Nanotube Bioconjugates

描述（由申请人提供）：碳纳米管（CNT）被生物分子功能化，因其在生物医学上的应用前景而备受关注，例如用作新型药物，用于治疗目的的DNA和蛋白质转运体。非共价相互作用广泛存在于碳纳米管生物偶联物中，对碳纳米管在水溶液中的溶解度和在活细胞中的内在化起着非常重要的作用。然而，碳纳米管生物系统中的这种弱相互作用还远远没有在分子水平上得到很好的理解。该项目的主要目标是利用最先进的基于第一性原理的工具，如密度泛函理论计算，量子和经典分子动力学模拟，很好地理解碳纳米管生物偶联物之间的非共价相互作用。该项目的目标是：

DESCRIPTION (provided by applicant): Carbon nanotubes (CNT), functionalized by biomolecules, are attracting much attention because of their promising biomedical applications, for instance, using as novel drug, DNA and protein transporters for therapy purposes. Non-covalent interactions widely exist in CNT-bioconjugates and play very important roles on solubility in aqueous solutions and internalization of CNT into living cells. However, such weak interactions in CNT-biosystems are far from being well understood at a molecular level. The major goal of the project is to well understand the non-covalent interactions among the CNT-bioconjugates with state-of-the-art first principles based tools such as density functional theory calculation, quantum and classical molecular dynamics simulations. The objectives of the project are: (1) to validate an appropriate density functional theory as well as an effective first principle-based protocol to describe non-covalent interactions and charge transfer between CNTs and biomolecules such as DNA bases, amino acids, polypeptides and so on; (2) to provide benchmark results at a molecular level for the nature of the non-covalent interactions between CNTs and biomolecules like DNA bases, amino acids, DNA oligonucleotides, and polypeptides; (3) to clarify a few important issues for the non-covalent interactions between CNT and DNA-protein systems via multi-scale molecular modeling and simulations, such as interaction mechanism, the major driving force, interaction dependence on the diameters and electronic structure of single-walled CNTs (SWCNTs), and interaction dependence on the composition and sequence of polypeptide and DNA oligonucleotides; (4) to well understand cellular internalization mechanisms of SWCNT-biomolecule conjugates into living cells. Development of new and efficient drug delivery system is very important to improve the therapeutic profile of drug molecules. The advancement of carbon nanotube functionalization has opened up new possibilities in this field. Theoretical investigations of the interface and interactions between biomolecules and CNT could provide understanding and description for CNT-bioconjugates at a molecular level. Such knowledge could eventually help design a new generation of drug delivery systems based on CNTs.