Lecithin-chitosan nanoparticles for co-delivery of curcumin and β-caryophyllene—potential applications in chronic wound care

Chronic skin wounds pose a significant challenge due to persistent inflammation, elevated oxidative stress, and high susceptibility to microbial colonization. To support wound healing, this study investigated lecithin-chitosan nanoparticles co-loaded with curcumin and β-caryophyllene, two natural compounds with complementary anti-inflammatory, antioxidative, and antimicrobial properties. Co-loading curcumin and β-caryophyllene produced near-spherical nanoparticles with consistent size distribution (200-240 nm) and favourable surface charge (+30-35 mV) for topical applications. The <i>in vitro</i> release studies showed gradual, sustained curcumin release over 24 h, with encapsulation modestly affecting permeation. Furthermore, ABTS and DPPH assays revealed strong radical scavenging activity of curcumin, comparable to vitamin E and slightly lower than vitamin C, supporting its potential to mitigate oxidative damage in chronic wounds. Anti-inflammatory activity was confirmed <i>via</i> nitric oxide inhibition in lipopolysaccharide-induced murine macrophages, where co-loaded nanoparticles significantly reduced NO production in a concentration-dependent manner. Cytotoxicity testing showed that while free curcumin reduced cell viability, the encapsulated compound was notably non-toxic. The nanoparticles also demonstrated strong antimicrobial activity against <i>Staphylococcus aureus</i>, reducing bacterial growth to nearly zero in the co-loaded formulation. These findings highlight curcumin and β-caryophyllene co-loaded lecithin-chitosan nanoparticles as a promising platform for topical chronic wound treatment, offering dual delivery and synergistic effects against inflammation, oxidative stress, and infection. To our knowledge, this is the first study to co-deliver curcumin and β-caryophyllene in lecithin-chitosan nanoparticles, enabling a unified antioxidant, anti-inflammatory, and antimicrobial strategy for chronic wound therapy.