Physico-chemical characterization and cytotoxicity evaluation of curcumin loaded in chitosan/chondroitin sulfate nanoparticles

In this study, chitosan (CTS)/chondroitin sulfate (CS) nanoparticles, both pure and curcumin-loaded, were synthesized by ionic gelation. This method is simple and efficient for obtaining nanoparticles with a low polydispersity index (0.151 ± 0.03 to 0.563 ± 0.07) and hydrodynamic diameter in the range of 175.7 ± 2.5 to 710.2 ± 8.9 nm, for this study. Samples have a relatively high zeta potential value, a fact that indicates that the colloidal system has good physical and chemical stabilities. The efficiency of the curcumin encapsulation in nanoparticles, which ranged from 62.4 ± 0.61% to 68.3 ± 0.88%, depends on the pH of the chitosan solution. The release of curcumin from the nanoparticles was enabled by a diffusion mechanism, with fast release in a phosphate buffer solution at pH 6.8. The assaying of cell viability by the MTT test showed that the presence of both free curcumin and curcumin in the nanoencapsulated form leads to a statistically significant reduction in the viability of A549 cells, by comparison with the control group. The most significant reductions in cell viability of 41.1% and 60.4% (p < 0.0001) were observed after 72 h, by using 40 μmol∙L− 1 free curcumin and curcumin encapsulated in CTS/CS nanoparticles with the chitosan solution at pH 6.0, respectively.