A mesoscopic model with molecular resolution is presented for dipalmitoyl phosphatidylcholine (DPPC) and palmitoyl oleoyl phosphatidylcholine (POPC) monolayer simulations at the air-water interface using many-body dissipative particle dynamics (MDPD). The parameterization scheme is rigorously based on reproducing the physical properties of water and alkane and the interfacial property of the phospholipid monolayer by comparison with experimental results. Using much less computing cost, these MDPD simulations yield a similar surface pressure-area isotherm as well as similar pressure-related morphologies as all-atom simulations and experiments. Moreover, the compressibility modulus, order parameter of lipid tails, and thickness of the phospholipid monolayer are quantitatively in line with the all-atom simulations and experiments. This model also captures the sensitive changes in the pressure-area isotherms of mixed DPPC/POPC monolayers with altered mixing ratios, indicating that the model is promising for applications with complex natural phospholipid monolayers. These results demonstrate a significant improvement of quantitative phospholipid monolayer simulations over previous coarse-grained models.

提出了一种具有分子分辨率的介观模型，用于使用多体耗散粒子动力学 (MDPD) 在空气-水界面处模拟二棕榈酰磷脂酰胆碱 (DPPC) 和棕榈酰油酰磷脂酰胆碱 (POPC) 单层。参数化方案严格基于再现水和烷烃的物理性质以及磷脂单分子层的界面性质，并与实验结果进行比较。这些 MDPD 模拟使用更少的计算成本，产生了与全原子模拟和实验类似的表面压力-面积等温线以及类似的压力相关形态。此外，可压缩模量、脂质尾部的有序参数和磷脂单层的厚度在数量上与全原子模拟和实验一致。该模型还捕获了混合比改变的 DPPC/POPC 单分子层的压力面积等温线的敏感变化，表明该模型有望用于复杂的天然磷脂单分子层。这些结果表明定量磷脂单层模拟比以前的粗粒度模型有显着改进。