Molecular Dynamics Simulations on Polymeric Nanocomposite Membranes Designed to Deliver Pipobromane Anticancer Drug

Abstract

Three chitosan (CS), polyethylene glycol (PEG) and polylactic acid (PLA) nanocomposite systems containing SiO2 nanoparticles and water molecules were designed by molecular dynamics (MD) simulations to deliver pipobromane (PIP) anticancer drug in order to discover the most appropriate drug delivery system (DDS) in aqueous medium which was analogous to the human body. The density for the CS matrix was 1.25 g/cm3 but it was decreased to 1.16 g/cm3 in PLA and 1.02 g/cm3 in PEG. The potential energies of the CS, PLA and PEG DDSs were near 195000, 3700 and –4600 kcal/mol while their related non-bond energies were around 14000, –150 and –6150 kcal/mol, respectively, indicating the PEG composite had the most negative energies whereas the most positive values belonged to the CS system. The CS system revealed the greatest fractional free volume (FFV) of 77.232% but PLA offered the smallest FFV (65.804%). The radial distribution function (RDF) data displayed that the PIP molecules had strongest H-bond interactions with the CS chains which reflected the drug molecules would diffuse the slowest inside the CS nanocomposite. The diffusion coefficients for the PLA, PEG and CS systems were equal to 0.0183×10–4, 0.0163×10–4 and 0.0154×10–4 cm2/s, respectively approving the slowest drug diffusion was happened in the CS cell which certified the most controlled and sustained drug delivery.