Molecular dynamics simulation study of chitosan and gemcitabine as a drug delivery system.

By using molecular dynamics (MD) simulation, biodegradable biopolymer chitosan as a carrier for the drug gemcitabine was investigated and the effect of three initial drug concentrations (10, 40, and 80%) on its loading efficiency was studied. Then water was added to the systems of drug and biopolymer and the effects of water on the interactions of drug and chitosan and on the drug loading efficiency were examined. From the results it was found that the maximum loading of the drug occurred at 40% of the drug concentration. The radial distribution function calculations indicated that in the absence of water molecules, the drug molecules were located at shorter distance from chitosan and the loading efficiency of the drug in these systems was higher.