Open Access

Julian David Friedl, Marcel Walther, Pia Katharina Vestweber, Jana Wächter, Patrick Knoll, Arne Matteo Jörgensen, Andreas Bernkop-Schnürch, Maike Windbergs

• To date, buccal administration of lipophilic drugs is still a major challenge due to their poor solubility in saliva and limited penetration into mucosal tissues. To overcome these limitations, we developed electrospun patches combining the benefits of mucoadhesive fibers and self-emulsifying drug delivery systems (SEDDS). The fiber system comprises a combination of mucoadhesive thiolated polyacrylic acid fibers and SEDDS-loaded fibers fabricated by parallel electrospinning. The resulting mucoadhesive electrospun SEDDS patches were systemically investigated for fiber characteristics, self-emulsification, mucoadhesion, drug penetration into porcine buccal tissue and biocompatibility. The patches showed high encapsulation efficiency for SEDDS without causing fiber defects or leakage. SEDDS incorporation enhanced the spinning process and reduced the fiber diameter and fiber size distribution. Hydration-dependent self-emulsification provided a controlled release of curcumin being encapsulated in nano-scaled o/w emulsion for over 3 h. Due to the thiolated polyacrylic acid fibers, the buccal residence time of patches was 200-fold prolonged. Further, they promoted a significantly increased drug penetration into buccal tissue compared to fiber patches without SEDDS. Finally, biocompatibility and improved therapeutic effects of curcumin-loaded patches on human keratinocytes and fibroblasts were confirmed. Mucoadhesive electrospun SEDDS patches represent a promising approach to overcome current challenges in the oromucosal delivery of lipophilic drugs to unlock their full therapeutic potential. Highlights • Self-emulsifying drug delivery systems (SEDDS) were electrospun into polymer fibers patches for oromucosal drug delivery. • High loading capacity of the fibers with SEDDS was shown (up to 50% of polymer weight). • 200-fold prolonged buccal patch residence time was achieved by parallel electrospinning of polyacrylic acid thiomer fibers. • SEDDS-loaded fibers ensured prolonged release of curcumin and led to 1200-fold increase in aqueous solubility. • In contrast to conventional fiber patches, SEDDS-loaded mucoadhesive fibers enabled deep mucosal penetration of curcumin.