Comparison of properties of farnesol and hydroxypropyl chitosan complexes obtained by chemical modification and physical loading

As an essential oil component, farnesol (Far) possesses biological activity. Nevertheless, its high hydrophobicity and volatility pose significant limitations to its practical application. Hydroxypropyl chitosan (HPCS) is a modified chitosan characterized by excellent solubility and a wealth of reactive groups. In this study, we used HPCS as the primary matrix to improve the stability and solubility of Far through chemical modification and physical loading. Subsequently, we comparatively analyzed the thermal stability, antioxidant activity and antibacterial activity of the two products. The derivatives (HPCS-Far-1–3) and nanoparticles (HPCS NPs, HPCS-Far NPs) were fabricated by bromide-mediated nucleophilic substitution and ionic gelation methods, respectively. The comparative analysis of these two derivatives presented potent antibacterial and antioxidant properties along with better solubility and thermal stability. This study is the first to compare the complex properties between chemical modification and physical loading, which offers valuable insight for the application of Far in different scenarios.