Annalisa Curcio, Fabiana Nano, Michele Pironti, Nicola Marchitto, Alberto Pannozzi, Lucia Laura Bilo, Adriana Romano, Gianfranco Raimondi
Objective: The aim of this study is to evaluate the influence of different vehicles in the permeability process of active ingredients in a topical composition containing cannabis sativa seed oil enriched in Cannabidiol (CBD), escin, bromelain, glucosamine sulphate, methylsulfonylmethane, methylsalicylate and Boswellia extract, designed for local treatment of musculoskeletal painful and inflammatory conditions.
Methods: The same amount of each active ingredients (1% w/w) has been dissolved in four different vehicles (G1: liquid paraffin, white petrolatum, cetostearyl alcohol, polyethylene glycol 1000; G2: water, propylene glycol, carbomer; G3: water, phenoxyethanol, caprylyl glycol, decylene glycol, carbomer; G4: water, phenoxyethanol, caprylyl glycol, decylene glycol, carbomer, glycerin). Permeability skin tests were carried out in modified Franz Diffusion Cells, using human epidermis as a membrane. Tested formulations were applied over the stratum corneum directly in the donor compartment of each cell, while receiver compartments were filled with degassed purified water/ ethanol solution (50/50, v/v). At predetermined times (1, 3, 5, 7, and 24 h), 200 μL samples were collected from the receiver compartment and analysed by HPLC.
Results: Results showed that there is an influence of vehicle composition on permeation/retention profile of active ingredients in the formulation. By switching from G1 to G4 preparation we found the best performing composition against the lipophilic ointment G1 in terms of active ingredients skin retention (p<0.05 G1 vs. all other preparations) and permeation rate (p<0.05 G1 vs. all other preparations), as measured with cumulative permeated amount at 24 h (Qp, 24) and retained amount at 24 h (Qr,24) parameters, respectively.
Conclusion: This study allowed us to choose G4 vehicle for final formulation of the topical gel composition containing cannabis sativa seed oil enriched in CBD, escin, bromelain, glucosamine sulphate, methylsulfonylmethane, methylsalicylate and Boswellia extract, named Cibides lipogel®.