A Collagen Pickering Emulsion-Coated Mycelium Film with Hydro-Responsive Toughness and Adhesion for Psoriasis Treatment via Tea Tree Oil Release

Psoriasis is a severe, chronic inflammatory skin disease that significantly impairs patients’ quality of life and can potentially be life-threatening. However, current treatments are often limited by strong side effects, short therapeutic efficacy, and a risk of secondary tissue damage. To address these limitations, this study developed a fully biomass-based, hydro-responsive adhesive dressing with controlled tea tree oil (TTO) release for psoriasis treatment. TTO was encapsulated within collagen Pickering emulsions (COLPE) and subsequently coated onto a mycelium (MYC) film to form a TTO-releasing MYC/COLPE composite patch. The optimal TTO concentration was determined to be 8%, selected based on a trade-off among encapsulation efficiency (75% at 6% TTO vs reasonably reduced to 55% at 8% TTO), droplet size uniformity (6.5 μm), and biocompatibility (cell viability >80%). The COLPE effectively encapsulated TTO and enabled sustained release. Upon hydration, the COLPE layer became adhesive, enabling the film to firmly adhere to the skin. Meanwhile, the hydrated MYC/COLPE dressing demonstrated a nearly fourfold enhancement in toughness from 2.5 MJ/m 3 in its dry state to 10.0 MJ/m 3 in its hydrated state, accompanied by improved flexibility, thereby ensuring robust mechanical support and excellent skin conformability. Antibacterial tests revealed over 90% inhibition rates against both Escherichia coli and Staphylococcus aureus . Biocompatibility tests indicated cell viability above 80% and a hemolysis rate below 5%, confirming favorable biosafety. In a mouse model of psoriasis, the MYC/COLPE film effectively alleviated psoriatic skin lesions. Overall, this work presents a promising therapeutic strategy for psoriasis and offers a paradigm for integrating fungal MYC and collagen in the design of functional wound dressings.