Evaluation and Selection of Gel Base for the Formulation of Dexpanthenol Products
Purpose: To formulate dexpanthenol gels with enhanced in vivo absorption properties via skin.
Methods: Carboxyvinyl derivatives (Carbopol 980 and Ultrez 10) and poloxamer (Lutrol F 127) were used as the hydrogel base in the formulations. Changes in rheological properties (apparent viscosity and penetration values) during the storage period were examined by Rheotest RN rotational viscometer and PNR12 penetrometer. In vitro release study using Franz diffusion cell was employed to compare the release characteristics of the formulated hydrogels with those of a reference cream.
Results: The flow curves of the gels with Carbopol 980 and Ultrez 10 showed pseudoplastic flow. Lutrol F 127 gels presented thixotropic behaviour. The consistency of the studied gels was in the following rank order: Lutrol F 127 > Ultrez 10 > Carbopol 980. In vitro results showed that dexpanthenol was released in lower amounts from the reference cream than from the three test gels. No significant differences were observed in the amount of active substance released from the gels due probably to the fact that Carbopol 980 and Ultrez 10 are both carboxyvinyl polymers. The highest amount of dexpanthenol was released from Lutrol F 127 gel.
Conclusion: The hydrogel made with Lutrol F 127 gel base possesses the best properties of all the gels and is recommended for the formulation of a suitable dexpanthenol gel.
Keywords: Hydrogel, Dexpanthenol, Carboxyvinyl polymers, Gels, Carbopol, Poloxamer, Rheology, Drug release, Penetrometer