Preparation and characterisation of gallic acid loaded carboxymethyl chitosan nanoparticles as drug delivery system for cancer treatment

Abstract Gallic acid (GA) is a natural phenolic compound with antioxidant, anti-proliferative, and anticancer effects. However, the potential of GA as an anticancer agent is restricted by its poor absorption, rapid elimination, and low bioavailability. Nanostructure-drug carriers have opened up a new field in cancer therapy by improving the efficacy of drugs. In this work, we developed a nanoformulation of GA in carboxymethyl chitosan (CMC). The particle size, surface charge and molecular structure of the CMC NPs loaded and unloaded with GA were measured using TEM, DLS and FTIR spectroscopy, respectively. The dielectric parameters (permittivity ε ′ and dielectric loss ε ″) were measured in the frequency range (0.1 Hz–5 MHz) at room temperature. Additionally, the in-vitro anti-cancer effects of the GA, CMC NPs, and GA-CMC NPs were tested against human colon carcinoma (HCT-116), human breast carcinoma (MCF-7), and normal skin fibroblast cells (BJ1) using MTT assay. TEM confirmed that the NPs have a spherical morphology within the size range of 15 nm. DLS studies revealed NPs with a mean diameter of 31.06 nm. The zeta potential results indicated the high suspension stability of the prepared nanoformulation. The FTIR results indicated the interaction between GA and CMC NPs. The dielectric study showed a decrease within the ε ″ and conductivity values of GA-CMC NPs which confirmed the successful encapsulation of GA within the CMC NPs. Cytotoxicity studies indicated that the GA-CMC NPs showed specific toxicity towards cancer cells and non-toxicity to normal cells. Overall, these results indicate that the GA-CMC NPs will be an efficient nanocarrier for delivering gallic acid to cancer cells.