Development of Eugenol-Embedded Calcium Citrate Nanoparticles as a Local Anesthetic Agent.

Eugenol is a major phenolic component derived from clove oil with potential medical applications. Of particular interest, it has been used as a therapeutic agent in topical applications because of its analgesic and local anesthetic properties. However, topical formulations of eugenol produce skin irritation, which limits its clinical applications. One promising strategy to overcome this disadvantage is by using a biocompatible material that could be an appropriate topical vehicle for eugenol. Researchers have recently focused on the development of eugenol-embedded calcium citrate nanoparticles (Eu-CaCit NPs) without adverse effects. The Eu-CaCit NPs were developed as a topical delivery system and their biocompatibility and penetration ability were evaluated. Eu-CaCit NPs at 1.2 mg/mL did not show cytotoxicity effects in human cells. Moreover, the Eu-CaCit NPs presented the ability to penetrate the dermis layer of the human intact skin following 12 h exposure. All the results concluded that Eu-CaCit NPs have shown a potential as a carrier for topical delivery of eugenol. These novel nanoparticles represent a promising alternative for topical application of local anesthetic with natural pain relievers.