3D-printed microfluidic chip for the preparation of glycyrrhetinic acid-loaded ethanolic liposomes

18-α-Glycyrrhetinic acid (GA) is a bioactive compound extracted from licorice that exhibits many biological and pharmacological effects such as anti-inflammatory and antioxidant activities on the skin. However, its lipophilic nature results in poor bioavailability that limits clinical applications. Liposomes, presenting the ability to carry both hydrophobic and hydrophilic payloads and a good cytocompatibility, are effective to overcome this barrier. Furthermore, the addition of permeation enhancers such as ethanol into liposomal formulations helps the diffusion of these systems through the skin barrier.

Here, we aimed to formulate GA-loaded ethanolic liposomes, using a natural soybean lecithin via a microfluidic approach. Using an FDM 3D printer we customized a microfluidic chip, and manufactured vesicles that presented spherical shape with a size of 202±5.2 nm, a good size distribution and good stability over a period of 30 days. After reaching a drug encapsulation efficiency of 63.15±2.2%, liposomes were evaluated for their cytocompatibility and skin permeation potentiality after hydrogelation using xanthan gum. The in vitro release and permeation studies were performed using Franz diffusion cells comparing two different media and three synthetic membranes including a polymeric skin-mimicking membrane.

The selected formulation presented no cytotoxicity and an increased permeation compared to GA saturated hydrogel. It could perform therapeutically better effects than conventional formulations containing free GA, as prolonged and controlled release topical dosage form, which may lead to improved efficiency and better patient compliance.

See the article

Author links open overlay panelMattia Tiboni, Serena Benedetti, Athanasios Skouras, Giulia Curzi, Diego Romano Perinelli, Giovanni Filippo Palmieri, Luca Casettari
International Journal of Pharmaceutics
https://doi.org/10.1016/j.ijpharm.2020.119436

Keywords: Topical drug delivery, Fused Deposition Modeling (FDM), Hydrogel, Strat-M®, Vertical Diffusion Cell, Human Keratinocyte (HaCaT)