In this study, we designed nanoparticles (NPs) based on polylactic acid glycolic acid modified with chitosan and folic acid to optimize the anti‐cancer, anti‐inflammatory, and antioxidant effects of arctiin (ARC), and we measured its effects on cancer cells, including colon cancer. NPs were synthesized using the W1/O/W2 double‐emulsion solvent evaporation method. Physicochemical characteristics of synthesized NPs (ARC‐PCF‐NPs), including average particle size, dispersity index (PDI), zeta potential (ZP), field emission scanning electron microscope figures, and encapsulation efficiency (EE), were evaluated. 2,2′‐Azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP) methods were carried out to determine the antioxidant properties of NPs. 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide assay was performed to investigate cytotoxicity effects on cancer cells and normal fibroblasts. Quantitative polymerase chain reaction was also performed on inflammatory and antioxidant genes. The obtained results indicated that the synthesized NPs have a size of 100 nm, a DPI of 0.36, a ZP of 26.30 mV, and EE was calculated at about 87.5%. The antioxidant influence of ARC‐PCF‐NPs was confirmed by inhibiting ABTS and DPPH free radicals and ferrous reduction in the FRAP method. Moreover, the reduction of inflammatory and antioxidant genes confirmed the anti‐inflammatory and antioxidant properties of NPs. These results indicate the modification of the surface of NPs in order to increase the bioavailability, stability, and effectiveness of medicinal compounds in therapeutic applications.