DescriptionUnderstanding the interactions between nanoparticles (NP) and soft, complex interfaces, such as lipid bilayers (LB), and high-density polymer grafted substrates, is important for many biological, and technological processes, as well as for assessing health threats related to nanoparticle commercialization. Adhesion, intake, and release of hydrophobic NPs by 1,2-dimyristoyl-sn-glycero-3-phosphocholine bilayers are explored, and the dynamics of unforced transport of NP across the LB is evaluated. NP intake may also cause cell instability that is studied by modeling the dynamics of the tension-induced hole formation in Np-loaded LBs. An NP size dependent relationship is established for the probability of membrane rupture within a given time as a function of the membrane tension. Next, the NP motion in polymer brush (PB) grafted channels is explored focusing on the process on NP chromatographic separation. . The existing theory, which considers NP motion in hard- wall channels with is extended for the case of PB-grafted substrates. Additionally, separation experiments are performed to develop a hybrid liquid chromatography model, which combines the hydrodynamic and size-exclusion chromatography approaches to predict the residence time in polymer-grafted chromatographic columns.