Numerical investigations of translocation characteristics of multiple silica nanoparticles across pulmonary surfactant monolayer

Abstract

Understanding translocation characteristics of multiple silica nanoparticles (SiNPs) across pulmonary surfactant (PS) is crucial for their applications in inhaled nanoparticle drugs. Therefore, we employed coarse-grained molecular dynamics method to simulate the translocation process of paired SiNPs (P-SiNPs). It is found that crossing or embedding process of 6 and 8 nm spherical P-SiNPs takes significantly longer due to cooperative effects, with times increased by 4.8–14.6 and 8.8–24.8 times, respectively. The influence of size differences between P-SiNPs is complex. Notably, 8 nm SiNP completes its crossing in a pinocytosis-like manner. The presence of same-sized ellipsoidal SiNPs significantly disrupts PS monolayer, and 8 nm ellipsoidal SiNP induces the formation of a crescent-shaped groove and even a pore. In conclusion, the translocation process of multiple SiNPs is cooperative process influenced by size, concentration, size differences, and shape. To mitigate potential toxic side effects, it is recommended to use smaller-sized spherical SiNPs as drug carriers.