The Design of Temperature and pH-Responsive Drug Delivery System Based on Cellulose and Aminated Cellulose by Computational and Experimental Methods

Abstract

In this study, molecular dynamics (MD) simulations were performed on cellulose and aminated cellulose. Obtained results show the presence of amine moieties and their protonation, positive charges and repulsive forces increase. As a result, the van der Waals and electrostatic interactions and hydrogen bonding number decrease. Then, paclitaxel was loaded through docking into the structures and was studied by MD simulations. The simulations were performed in several protonation states along with 25∘C, 37∘C, 42∘C and 50∘C temperatures. The carrier/ligand system behaviors were analyzed. The results indicate the increase of temperature and protonation decrease hydrogen bonding number between drug and carrier and increase binding free energy. At last, to compare the simulations results, paclitaxel was loaded in cellulose and aminated cellulose and investigated in the in vitro release at two conditions (37∘C, pH 7.4, and 42∘C, pH 5). Experimental results prove computational results as pH/temperature-responsive system.