Preparation of berberine hydrochloride-Ag nanoparticle composite antibacterial dressing based on 3D printing technology.

In recent years, Ag nanoparticle (Ag NP)-loaded antibacterial dressings have attracted much attention in high-level medical dressings. However, the high cytotoxicity of Ag NP has always been a problem. In this paper, we examined the improvement of antibacterial activity of berberine hydrochloride (BBR) with Ag NP, the results showed that the combined use of BBR and Ag NP can effectively reduce the dosage of Ag NP while ensuring the inhibition of bacterial growth, thus an intermediate layer dressing containing combined drugs were prepared. At the same time, the top dressing of polyvinyl alcohol (PVA) solid film and the PVA bottom dressings with three kinds of leakage structures were prepared by 3D printing technology. Three kinds of PVA bottom dressings showed high quality consistency, and the greater the number of leak holes, the higher the porosity value of the dressing, while the swelling ratio value of the bottom layer dressing with three holes was the lowest. Finally, three types of BBR-Ag NP composite antibacterial dressings (3D-BBR-Ag NP) can be obtained by self-assembling of the top dressing, the intermediate layer dressing, and the bottom dressings with three kinds of leakage structures. The cumulative drug release results showed that dressing with more holes had a faster drug release rate compared to the other two ones with fewer leakage holes. Besides, five drug release kinetic models were used to investigate the cumulative BBR release profiles for three types of 3D-BBR-Ag NP. And the three types of composite dressings showed strong antibacterial activity after 6 h of cultivation with staphylococcus aureus. The study showed that the antibacterial activity of the self-assembled dressing prepared by combination of BBR with Ag NP can be improved, and the drug release rate of the hydrogel dressing can be flexibly controlled through 3D printing technology.