Juniperus oxycedrus L. ssp. essential oil microneedles: a promising antimicrobial and wound healing activity

The use of essential oil (EO) in treating infected wounds is still challenging. A lot of effort has been made to make such an application more convenient. Recently, microneedles (MNDs) have been considered as a smart dermal delivery system to overcome the poor absorption and distribution, low bioavailability, and skin penetration of some drugs. The aim of our study is to evaluate the wound healing activity of juniper-EO-loaded MNDs (EO MNDs) against wounds with bacterial and fungal infection. The Polyvinylpyrrolidone (PVP) MNDs were prepared using the gel-filled mold technique and loaded with juniper EO. In vivo models were created and wounds on rats were infected with two clinically isolated bacterial strains Pseudomonas aeruginosa and Staphylococcus aureus. Furthermore, Candida albicans was used to mimic fungal infection and juniper EO MNDs were tested. The obtained results showed an improvement in wound healing which started from the third day after application of the juniper EO MNDs, and at the sixth day post-infection, the treated wounds were significantly smaller than untreated wounds. A complete healing was shown by the 12th day after infection. Furthermore, our cytotoxicity results showed a cytotoxic effect of juniper EO MNDs on epithelial cells, which explained the faster wound healing in rats. Our study showed that juniper EO MNDs represent a novel strategy in EO delivery with minimal invasion. Juniper EO MNDs demonstrated significant antimicrobial activity against both the bacterial strains Pseudomonas aeruginosa and Staphylococcus aureus and against one fungal strain, Candida albicans. Finally, application of juniper EO MNDs exerted promising activity in the treatment and healing of wound infection.