Molecular dynamics simulations on chitosan/graphene nanocomposites as anticancer drug delivery using systems

Abstract

Several chitosan (CS) drug delivery systems (DDSs) were designed by molecular dynamics (MD) simulations. The systems were composed of pure graphene (G), P-doped (GP) or N-doped (GN) graphene nanosheets for the anticancer drug cyclophosphamide (CP) with the aim of discovering the most appropriate drug carrier. Furthermore, the temperature influence was investigated on the systems characteristics through performing the simulations at four different temperatures including 25, 35, 45 and 55 °C. The diffusion coefficients and mean square displacements (MSDs) were boosted with the temperature increase. At 55 °C, the CS-G-CP exhibited the greatest diffusion coefficient (0.0658 × 10–5 cm2/s) but the CS-GN-CP had the smallest diffusion coefficient of 0.0553 × 10–5 cm2/s and the CS-GP-CP illustrated a medium amount (0.0595 × 10–5 cm2/s) indicating the most controlled/sustained drug diffusion could occur in the CS-GN-CP which could allow the most efficient drug delivery. Moreover, to evaluate the effects of PEG chains and VC molecule on the drug delivery capacity of the CS-GN-CP cell, they were added to the this system and the CS-GN-CP-PEG2-VC was nominated as the best DDS working at 35 °C (close to the human body temperature) due to it had a relatively high drug loading capacity as well as suitable CP diffusion coefficient and FV, FFV values.