In this work, at first, in order to find the most stable conformers of the two types of anticancer cytarabine (CYT) and gemcitabine (GEM) drugs, the potential energy curves for rotation around the C1′-N bond were explored at M06-2X/6–311 + + G(2d,2p) level of theory. Adsorption of the most stable conformers of CYT and GEM drugs on the BNNT surface was explored. Depending on the orientation of CYT and GEM drugs on the outside surface of the BNNT, two different types of drug-BNNT adsorption complexes (A and B) were found on the potential energy surface. Dispersion corrected adsorption energies at M06-2X/6–31 + G(d)-GD3 level were in the range − 19.7 to − 26.1 kcal mol⁻¹ for A₁–A₄ and − 21.7 to − 24.6 kcal mol⁻¹ for B₁–B₄. The results show that adsorptions of CYT and GEM drugs on the BNNT surface in the water solvent are energetically favorable process. The structural and electronic density properties, charge transfer values, global reactivity descriptors and the molecular electrostatic potential maps of the drug-BNNT complexes were evaluated. It is anticipated that the complex formation accompanied by charge transfer between BNNT and drugs and the decrease in the HOMO − LUMO energy gap. The NCI (non-covalent interaction) analysis shows the role and importance of the cooperative π − π stacking and H-bonding interactions on the adsorption of drugs on the BNNT surface.

在这项工作中，首先，为了找到这两种抗癌阿糖胞苷最稳定的构象（CYT）和吉西他滨（GEM）的药物，为各地C1'-N键旋转的势能曲线在M06-进行了探讨2X / 6–311 + + G（2d，2p）的理论水平。探索了CYT和GEM药物最稳定构象异构体在BNNT表面的吸附。根据CYT和GEM药物在BNNT外表面上的方向，两种不同类型的药物-BNNT吸附复合物（A和B）被发现在势能表面上。色散校正吸附能在M06-2X / 6-31 + G（d）-GD3水平分别在范围- 19.7至- 26.1千卡摩尔^-1为阿₁ -A ₄和- 21.7至- 24.6千卡摩尔^-1为B ₁ –B ₄。结果表明，CYT和GEM的吸附在水溶剂中，BNNT表面的药物在能量上是有利的过程。评价了药物-BNNT配合物的结构和电子密度特性，电荷转移值，整体反应性描述符和分子静电势图。可以预料，复合物的形成会伴随BNNT和药物之间的电荷转移以及HOMO-LUMO能隙的减小。NCI（非共价相互作用）分析表明，π-π堆积和H键相互作用对BNNT表面药物吸附的作用和重要性。