Biopolymers and pilocarpine interaction study for use in drug delivery systems (DDS)

This work aimed at the investigation of pilocarpine’s interaction in the association of cashew gum (CG) and chitosan (CH) biopolymers because of mucoadhesive and prolonged release properties of this polymeric system. To elucidate this issue, characterization techniques, such as DSC, TG, XRD, IR, were applied besides DFT B3LYP/6-31++G(d,p) computational calculations. According to this approach, CG interacts with pilocarpine having a protective thermal effect on the drug and CH can reduce its thermal stability. These interactions occur, preferably, between a carbonyl group from pilocarpine and hydroxyl groups from biopolymers in which hydrogen bonds are involved. Thus, this work was able to identify interactions between the drug and the biopolymers and how, in a molecular approach, they occur. These results allow for the full understanding of the influence of each biopolymer for future pilocarpine-release systems.