Healing activity of hydrogel containing nanoemulsified ß-caryophyllene.

ß-caryophyllene is a sesquiterpene present in the oil of many plant species, such as Copaifera sp., which has been shown to possesses potent anti-inflammatory action; however, its healing activity remains under study. The objectives of the present study were to produce a nanoemulsion containing ß-caryophyllene followed by a hydrogel containing nanoemulsified ß-caryophyllene, to evaluate the permeation profile in vitro, and to assess the in vivo healing activity, which is so far unexplored in the literature for pure ß-caryophyllene and in pharmaceutical formulation. The nanoemulsion was obtained through high-pressure homogenization and the hydrogel by direct dispersion with hydroxyethylcellulose. Both formulations were characterized according to droplet size, polydispersity index, volume-weighted mean diameters, particle distribution, droplets diameters tracking, zeta potential, viscosity and bioadhesion behavior. ß-caryophyllene content was determined by gas chromatography coupled with mass spectrometry (GC/MS). Both formulations presented a nanometric droplet size, negative zeta potential, high ß-caryophyllene content, and were stable for 60 days. In agreement with the viscosity results, the hydrogel containing the ß-caryophyllene nanoemulsion showed superior bioadhesiveness than the nanoemulsion. The skin permeation study in Franz cells demonstrated that isolated ß-caryophyllene was unable to cross the stratum corneum and that its nanoemulsification promoted its permeation. On the other hand, in the simulated deeply wounded skin (dermis), no significant differences were observed between the formulations and isolated ß-caryophyllene with respect to the amount of marker retention in the dermis, suggesting saturation of this skin layer. For the study of healing activity, the dorsal wound model was performed with an evaluation of the lesion size, anti-inflammatory markers, and antioxidant activity. The initial closure of the wound was achieved sooner in the group treated with the hydrogel containing the ß-caryophyllene nanoemulsion, indicating its anti-inflammatory effect. The histological analysis indicated that on day 12 day of the lesion, the hydrogel presented similar results to those of the positive control group (Dersani® oil), proving effectiveness in cutaneous tissue repair.

Ex Vivo Conjunctival Retention and Transconjunctival Transport of Poorly Soluble Drugs Using Polymeric Micelles.

This paper addresses the problem of ocular delivery of lipophilic drugs. The aim of the paper is the evaluation of polymeric micelles, prepared using TPGS (d-α-Tocopheryl polyethylene glycol 1000 succinate), a water-soluble derivative of Vitamin E and/or poloxamer 407, as a vehicle for the ocular delivery of dexamethasone, cyclosporine, and econazole nitrate. The research steps were: (1) characterize polymeric micelles by dynamic light scattering (DLS) and X-ray scattering; (2) evaluate the solubility increase of the three drugs; (3) measure the in vitro transport and conjunctiva retention, in comparison to conventional vehicles; (4) investigate the mechanisms of enhancement, by studying drug release from the micelles and transconjunctival permeation of TPGS; and (5) study the effect of micelles application on the histology of conjunctiva. The data obtained demonstrate the application potential of polymeric micelles in ocular delivery, due to their ability to increase the solubility of lipophilic drugs and enhance transport in and across the conjunctival epithelium. The best-performing formulation was the one made of TPGS alone (micelles size ≈ 12 nm), probably because of the higher mobility of these micelles, an enhanced interaction with the conjunctival epithelium, and, possibly, the penetration of intact micelles.