Spherical PEG/SiO2 promising agents for Lamivudine antiviral drug delivery, a molecular dynamics simulation study.

Spherical nanocarriers can lead to a bright future to lessen problems of virus infected people. Spherical polyethylene glycol (PEG) and spherical silica (SiO2) are novel attractive nanocarriers as drug delivery agents, especially they are recently noticed to be reliable for antiviral drugs like anti-HIV, anti-covid-19, etc. Lamivudine (3TC) is used as a first line drug for antiviral therapy and the atomic view of 3TC-PEG/SiO2 complexes enable scientist to help improve treatment of patients with viral diseases. This study investigates the interactions of 3TC with Spherical PEG/SiO2, using molecular dynamics simulations. The mechanism of adsorption, the stability of systems and the drug concentration effect are evaluated by analyzing the root mean square deviation, the solvent accessible surface area, the radius of gyration, the number of hydrogen bonds, the radial distribution function, and Van der Waals energy. Analyzed data show that the compression of 3TC is less on PEG and so the stability is higher than SiO2; the position and intensity of the RDF peaks approve this stronger binding of 3TC to PEG as well. Our studies show that PEG and also SiO2 are suitable for loading high drug concentrations and maintaining their stability; therefore, spherical PEG/SiO2 can reduce drug dosage efficiently.

Structural and dynamical properties of Palmitoyl-Oleoyl phosphatidylserine lipid nanotubes containing cholesterols and PEGylated dioleoyl Phosphatidylethanolamine: A Coarse-Grained molecular dynamics simulation

Lipid nanotubes (LNTs) are a class of lipid-based drug delivery systems (LBDDSs). Reports indicate that LBDDSs are effective systems in drug delivery to deal with COVID-19. The rational design of LNTs requires a deeper understanding of their structural properties in various influential factors such as lipid composition and PEGylation. This work uses coarse-grained molecular dynamics simulation to study the structural/dynamical properties of palmitoyl-Oleoyl phosphatidylserine (POPS) LNTs. To this end, the density distribution profiles are examined to evaluate of diameters and thicknesses of LNTs. The results show that adding cholesterol to LNT leads to lipid tail regularity, increasing the bilayer thickness and LNT diameter. PEGylation tends to increase irregularities of lipid chains, reduce the molecular packing and increase lipids dynamics. Our calculations predicted that manipulating LNT composition can be used to obtain favorable structural/dynamical properties and desired dimensions.