Section of Nano and Biophysics, Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
Boreskov Institute of Catalysis, Russian Academy of Sciences, Novosibirsk, Russia.
Eur Biophys J. 2023 Feb;52(1-2):121-127. doi: 10.1007/s00249-023-01633-4. Epub 2023 Feb 22.
In applications of bio-inspired nanoparticles (NPs), their composition is often optimised by including ionizable lipids. I use a generic statistical model to describe the charge and potential distributions in lipid nanoparticles (LNPs) containing such lipids. The LNP structure is considered to contain the biophase regions separated by narrow interphase boundaries with water. Ionizable lipids are uniformly distributed at the biophase-water boundaries. The potential is there described at the mean-filed level combining the Langmuir-Stern equation for ionizable lipids and the Poisson-Boltzmann equation for other charges in water. The latter equation is used outside a LNP as well. With physiologically reasonable parameters, the model predicts the scale of the potential in a LNP to be rather low, smaller or about [Formula: see text], and to change primarily near the LNP-solution interface or, more precisely, inside an NP near this interface because the charge of ionizable lipids becomes rapidly neutralized along the coordinate towards the center of a LNP. The extent of dissociation-mediated neutralization of ionizable lipids along this coordinate increases but only slightly. Thus, the neutralization is primarily due to the negative and positive ions related to the ionic strength in solution and located inside a LNP.
在仿生纳米粒子 (NPs) 的应用中，通常通过包含可离子化脂质来优化其组成。我使用通用统计模型来描述含有此类脂质的脂质纳米颗粒 (LNP) 中的电荷和电势分布。LNP 结构被认为包含由窄相间边界与水隔开的生物相区域。可离子化脂质均匀分布在生物相-水边界处。电势在平均场水平上进行描述，结合了可离子化脂质的 Langmuir-Stern 方程和水中其他电荷的 Poisson-Boltzmann 方程。后者方程也在 LNP 之外使用。使用生理上合理的参数，该模型预测 LNP 中的电势幅度相当低，约为 [Formula: see text]，并且主要在 LNP-溶液界面附近或更准确地在 NP 内部发生变化，因为可离子化脂质的电荷沿坐标向 LNP 中心迅速中和。沿着这个坐标的可离子化脂质的去质子化介导的中和程度增加但仅略有增加。因此，中和主要是由于与溶液中离子强度相关的带负电和带正电的离子，并位于 LNP 内部。
