Atomistic molecular dynamics simulations are carried out to investigate the structure, dynamics, and hydrogen bonding of polyelectrolyte dendrimers dissolved in a phosphate solution. Our findings indicate that the size, shape, and diffusion coefficient of the fifth-generation dendrimer weakly depend on phosphate concentrations and valences, consistent with the recent experiment (Kéri et al. Phys.Chem.Chem.Phys.,2017, 19, 11,540). Rather than H₂PO₄⁻, HPO₄²⁻ is observed to be tightly bound to the terminal of dendrimer, originating from the strong electrostatic attraction and hydrogen bonding. Further analysis reveals that hydrogen bonds mostly form between phosphates and primary aminic nitrogen atoms (as donors) at the terminal of PAMAM. And a revision of interaction mode between phosphate ions and dendrimer is suggested. This study provides fundamental insight into the behavior of charged dendrimers in phosphate buffer solutions.

进行原子分子动力学模拟以研究溶解在磷酸盐溶液中的聚电解质树枝状聚合物的结构，动力学和氢键。我们的发现表明，第五代树状大分子的大小，形状和扩散系数与磷酸盐浓度和化合价之间的关系微弱，这与最近的实验一致（Kéri等，Phys.Chem.Chem.Phys。，2017，19，11,540）。而不是ħ ₂ PO ₄ ^-，HPO ₄ ^2-观察到由于强的静电引力和氢键而紧密结合到树枝状聚合物的末端。进一步的分析表明，氢键主要在PAMAM末端的磷酸盐和伯氨基氮原子（作为供体）之间形成。并建议修改磷酸根离子与树枝状聚合物之间的相互作用方式。这项研究为带电树枝状聚合物在磷酸盐缓冲溶液中的行为提供了基本的见识。