Preparation and Properties of Chitosan Complexes Consisting of Artemisia argyi Volatile Oil Nanoemulsion

<i>Artemisia argyi</i> volatile oil (AAVO) is a kind of natural oil with abundant active components and remarkable medicinal and healthcare value. However, AAVO has low solubility, stability, and bioavailability. Here, to address these issues, a nanoemulsion system of <i>Artemisia argyi</i> volatile oil (AAVO-Ne) is constructed using phase transition titration, and the conditions are continuously optimized to combine it with chitosan, forming a chitosan composite of the volatile oil nanoemulsion (AAVO-NeCs). The structure was analyzed using Fourier transform infrared (FT-IR) spectroscopy, and the performance was evaluated through in vitro antibacterial tests, in vitro release experiments, and antioxidant assays. The results indicated that the typical characteristic absorption peaks of AAVO shifted in the AAVO-Ne spectrum and new absorption peaks appeared in the AAVO-NeCs, which implied that the formation of AAVO-NeCs involved not only a physical encapsulation process but also certain chemical interactions, thus enhancing the stability and bioactivity of the composites. Compared to AAVO, AAVO-NeCs exhibited a 1.87-fold increase in antibacterial activity against antibiotic-resistant bacteria. Meanwhile, the in vitro release study demonstrated that AAVO-NeCs exhibited a biphasic release pattern. Compared to AAVO-Ne and AAVO, AAVO-NeCs also showed a significant enhancement in antioxidant activity. Overall, AAVO-NeCs demonstrate improved solubility and efficacy of AAVO, as well as high-efficiency delivery, antibacterial, sustained-release, and antioxidant properties. These attributes position AAVO-NeCs as a promising candidate for applications in drug delivery, food preservation, and other fields, offering innovative solutions and contributing to the sustainable development of related industries.